9. xml query languages iii â€“ xquery

XML Databases9 XML Query Languages III ndash

Silke EcksteinAndreas KupferInstitut fuumlr InformationssystemeTechnische Universitaumlt Braunschweighttpwwwifiscstu-bsde

9 XML Query Languages III ndashXQuery

91 Introduction

92 Preliminaries

93 Iteration (FLWORs)

9 XQuery

94 FLWOR Semantics

95 Constructing XML Fragments

96 User-Defined Functions

97 Overview and References

XML Databases ndash Silke Eckstein ndash Institut fuumlr Informationssysteme ndash TU Braunschweig 2

bull XQuery

ndash XQuery is a truly declarative language specifically designed for the purpose of querying XML data

ndash As such XML assumes the role that SQL occupies in the context of relational databases

ndash XQuery exhibits properties known from database (DB) languages as

91 Introduction

ndash XQuery exhibits properties known from database (DB) languages as well as from (functional) programming (PL) languages

ndash The language is designed and formally specified by the W3C XQuery Working Group (httpwwww3orgXMLXQuery)

bull The first working draft documents date back to February 2001 TheXQueryspecification has become a W3C Recommendation in January 2007

bull Members of the working group include Dana FlorescuDB Ioana ManolescuDB Phil WadlerPL Mary FernandezDB+PL Don ChamberlinDB (the father of SQL) Jeacuterocircme SimeonDB Michael RysDB and many others

XML Databases ndash Silke Eckstein ndash Institut fuumlr Informationssysteme ndash TU Braunschweig 3[Gru08]

bull 12 Programming Language 12 Query Languagendash XQuery is a hybrid exhibiting features commonly found in programming as well as database query languages

bull Programming language features

explicit iteration and variable bindings (

91 Introduction

ndash explicit iteration and variable bindings (forinletin)

ndash recursive user-defined functions

ndash regular expressions strong [static] typing

ndash ordered sequences (much like lists or arrays)

bull Database query language features

ndash filtering

ndash grouping joins expressed via nested for loops


bull History of XQuery

91 Introduction


bull XQuery-Preliminariesndash Remember XPath is part of XQuery (as a sublanguage)ndash Some constructs that have not previously been discussed yet are not within the core of our focus on XQuery include

bull Comparisons any XQuery expression evaluates to a

92 Preliminaries

bull Comparisons any XQuery expression evaluates to a sequence of items Consequently many XQuery concepts are prepared to accept sequences (as opposed to single items)


General comparisonsThe general comparison withᶿe1 e2

yields true() if any of the items in the sequences e12 compare

true (existential semantics)

= = lt lt= gt=gtᶿ isin

92 Preliminaries

bull Comparisons General comparison examples

(123) gt (245) rArrrArrrArrrArr true()

(123) = 1 rArrrArrrArrrArr true()

() = 0 rArrrArrrArrrArr false()

2 lt= 1 rArrrArrrArrrArr false()



ndash The six value comparison operators eq ne lt le ge gtcompare single items by value (atomization)


(12) = (12) rArrrArrrArrrArr true()

not((12) = (12)) rArrrArrrArrrArr false()

Value comparisons

2 gt 10 rArrrArrrArrrArr true()

ltxgt42ltxgt eq ltygt42ltygt rArrrArrrArrrArr true()

(01) eq 0 rArrrArrrArrrArr (type error)

bull More on comparisons

ndash Note The existential semantics of the general comparison operators may lead to unexpected behavior

92 Preliminaries

a) For an item-by-item comparison use deep-equal()


Surprises

(123) = (13) rArrrArrrArrrArr true()a

(21) = 1 rArrrArrrArrrArr true() or (impl dependent)

bull Node comparisons

92 Preliminaries

based on identity and document order

e1 is e2 nodes e12 identical

e1 ltlt e2 node e1 before e2

e1 gtgt e2 node e1 after e2

ndash Node comparison examples


ltxgt42ltxgt eq ltxgt42ltxgt rArrrArrrArrrArr true()

ltxgt42ltxgt is ltxgt42ltxgt rArrrArrrArrrArr false()

root(e1) is root(e2) rArrrArrrArrrArr nodes e12 in same tree

let $a = ltxgtltygtltxgt

return $a ltlt $ayrArrrArrrArrrArr true()

bull Working with sequencesndash XQuery comes with an extensive library of builtinfunctions to perform common computations over sequences

bull Common sequence operations

92 Preliminaries

Function Example

count count((042)) rArrrArrrArrrArr 3



max max((042)) rArrrArrrArrrArr 4

subsequence subsequence((1357)23) rArrrArrrArrrArr (357)

empty empty((042)) rArrrArrrArrrArr false()

exists exists((042)) rArrrArrrArrrArr true()

distinct-values distinct-values((4424)) rArrrArrrArrrArr (42)

to (1 to 10)[ mod 2 eq 1] rArrrArrrArrrArr (13579)

bull Arithmeticsndash Only a few words on arithmetics ndash XQuery meets the common expectation here Points to note1 Infix operators + - lowastlowastlowastlowast div idiv (integer division)2 operators first atomize their operands then perform

promotion to a common numeric type

92 Preliminaries

promotion to a common numeric type3 if at least one operand is () the result is ()


Examples and pitfalls

ltxgt1ltxgt + 41 rArrrArrrArrrArr 420

() 42 rArrrArrrArrrArr ()

(12) - (23) rArrrArrrArrrArr (type error)

x-42 rArrrArrrArrrArr childx-42 (use x˽-˽42)

xy rArrrArrrArrrArr childxchildy (use x div y)

91 Introduction

92 Preliminaries

93 Iteration (FLWORs)ndash Foor loop

ndash Variable bindings

9 XQuery


ndash Where clause

94 FLWOR Semantics





bull XQuery Iteration FLWORsndash Remember that XPath steps perform implicit iteration in cse evaluation of e is iterated with bound to each item in cs in turn

ndash XPath subexpressions aside iteration in XQuery is explicit via the FLWOR (flower) construct


explicit via the FLWOR (flower) constructbull The versatile FLWOR is used to express

ndash nested iteration

ndash joins between sequences (of nodes)

ndash groupings

ndash orderings beyond document order etc

bull In a sense FLWOR assumes the role of the SELECT-FROM-WHERE block in SQL


bull FLWOR Iteration via forin

ndash Explicit iteration


Explicit iteration is expressed using the forin construct a

for $v [at $p] in e1


for $v [at $p] in e1 return e2

If e1 evaluates to the sequence (x1xn) the loop body e2 is

evaluated n times with variable $v bound to each xi [and $pbound to i ] in order The results of these evaluations are concatenated to form a single sequence

a the construct at $p is optional


Iteration examples

for $x in (321)

return ($xlowastlowastlowastlowast)rArrrArrrArrrArr (3lowastlowastlowastlowast2lowastlowastlowastlowast1lowastlowastlowastlowast)

for $x in (321)

return $xlowastlowastlowastlowastrArrrArrrArrrArr (321lowastlowastlowastlowast)

for $x in (321)

return for $y in (ab) rArrrArrrArrrArr(3a3b

2a2b


return for $y in (ab)

return ($x$y)

rArrrArrrArrrArr 2a2b

1a1b)

FLWOR Abbreviations

for $v1 in e1return

for $v2 in e2return e3

equivequivequivequiv

for $v1 in e1for $v2 in e2return e3


for $v1 in e1$v2 in e2

return e3



Purpose of this query Qmax( for $i in csdescendant-or-self[not()]

return count($iancestor) )

A sample cs ldquoAnnotatedrdquo sample cs


A sample csa

b c

d

e g h

f

ldquoAnnotatedrdquo sample csa

b

e

c

d

g h

f

1

3 3 3

Answer

bull FLWOR Iteration via forin ndash Return every other item in sequence


These queries both return the items at odd positions in the inputsequence e

for $i in (1 to count(e))[ mod 2 eq 1]

bull Remember ebv(0) = false()ebv effective boolean value



return e[$i]

for $i at $p in e

return if ($p mod 2)

then e[$p]

else ()

bull FLWOR Variable Binding via let =

ndash Note that in the examples on the last slide expression e is re-evaluated count(e) 2 times although e is constant in the loop


Variable bindingsThe result of evaluating an expression e may be bound to a variable $v

bull for and let clauses may be freely intermixed


Variable bindingsThe result of evaluating an expression e1 may be bound to a variable $vvia let

let $v = e1return e2

evaluates e2 with free occurrences of $v replaced by e1

bull FLWOR Variable Binding via letbull bull bull =


Iteration vs variable binding

for $x in (321)

return ($x)

rArrrArrrArrrArr (321

)

let $x = (321) rArrrArrrArrrArr (321)


let $x = (321)

return ($x)

rArrrArrrArrrArr (321)

Every other item revisited (flip back two slides)The following hoists the constant e out of the loop body

let $seq = ereturn for $i at $p in $seq


then $seq[$p]

else ()

bull Adding a where clause

ndash Inside loop bodies the idiom if (p) then e else ()

is so common that FLWOR comes with a SQL-like where clause to address this


A where clause


A where clauseIf ebv(p) evaluates to false() under the current variable bindings the

current iteration does not contribute to the result

for $v in e1where p

return e2

equiv

for $v in e1return if (p)

then e2else ()

bull Explicit vs implicit iterationndash XPath implicit iteration

ndash Equivalent nested FLWOR blocks


a[b = foo]c[2]d[e = 42]

for $a in a

ndash NB Unlike the XPath step operator for does not change the context item


for $a in a

where $ab = foo

return for $c at $p in $ac

where $p = 2

return for $d in $cd

where $de = 42

return $d

bull FLWOR Reorder iteration result via order byndash In a FLWOR block for $v in e1 return e2 the order of e1determines the order of the resulting sequence


Reordering via order by

In the FLWOR block


In the FLWOR block

the value (atomization) of e3 determines the order in which the bindingsof $v are used to evaluate e2

for $v in e1order by e3 [ascendingdescending][empty greatestleast]return e2

bull FLWOR Reordering examples


An order by no-op reordering by sequence order

for $x at $p in (53142)

order by $p

return $x



All bound variables in scope in order by

for $x at $p in (53142)

order by $p + $x

return $x


Reordering as in SQLs ORDER BY

for $x at $p in (53142)

order by $x

return $x


bull FLWOR Reordering examplesndash Value-based reordering of an XPath step result


This query reorders the result of the XPath location step descendantb

based on (string) value Which result is to be expectedlet $a = ltagt

ltb id=0gt42ltbgt

ltb id=1gt5ltbgt


ltb id=1gt5ltbgt

ltb id=2gt

ltb id=3gt3ltbgt

ltb id=4gt1ltbgt

ltagt

for $b in $adescendantb

order by $btext() empty greatest

return $bid

Answer

91 Introduction

92 Preliminaries


9 XQuery

94 FLWOR Semantics





bull FLWOR semantics tuple spacendash In the W3C XQuery specification the interaction of the five clauses of a FLWOR (for-let-where-order by-return) block is formally explained by means of a tuple space

94 FLOWR Semantics

means of a tuple spacebull Size of tuple space equiv number of iterations performed by FLWOR block

bull The fields of the tuples represent for each iteration

1 forlet variable bindings

2 the outcome of the where clause

3 the value of the reordering criterion and

4 the value returned by the return clause


bull FLWOR semantics tuple space (1)ndash Sample FLWOR block

94 FLOWR Semantics

for $x at $p in reverse(1 to 10)

let $y = $x $x

where $y lt= 42

order by 5 - $p

return ($p$x)

$x $p $y where order by return

10 1 100 false 4 (110)

1 Complete tuple space


return ($p$x) 10 1 100 false 4 (110)

9 2 81 false 3 (29)

8 3 64 false 2 (38)

7 4 49 false 1 (47)

6 5 36 true 0 (56)

5 6 25 true -1 (65)

4 7 16 true -2 (74)

3 8 9 true -3 (83)

2 9 4 true -4 (92)

1 10 1 true -5 (101)

bull FLWOR semantics tuple space (2)2 Filtering where clause ($y lt= 42)

94 FLOWR Semantics


10 1 100 false 4 (110)

9 2 81 false 3 (29)

8 3 64 false 2 (38)


8 3 64 false 2 (38)

7 4 49 false 1 (47)

6 5 36 true 0 (56)

5 6 25 true -1 (65)

4 7 16 true -2 (74)

3 8 9 true -3 (83)

2 9 4 true -4 (92)

1 10 1 true -5 (101)

bull FLWOR semantics tuple space (3)3 Reordering order by clause

94 FLOWR Semantics


1 10 1 true -5 (101)

2 9 4 true -4 (92)

3 8 9 true -3 (83)

4 To emit the final result scan the tuple space in the order specified by the order by column and concatenate the return column entries

(1019283746556)

ndash Observation some values have been computed but never used


3 8 9 true -3 (83)

4 7 16 true -2 (74)

5 6 25 true -1 (65)

6 5 36 true 0 (56)

bull FLWOR populate tuple space lazily (1)ndash Sample FLWOR block

94 FLOWR Semantics


let $y = $x $x

where $y lt= 42

order by 5 - $p

return ($p$x)

$x $p $y

10 1 100

1 Populate variable bindings only


return ($p$x) 10 1 100

9 2 81

8 3 64

7 4 49

6 5 36

5 6 25

4 7 16

3 8 9

2 9 4

1 10 1

bull FLWOR populate tuple space lazily (2)2 Evaluate where clause ($y lt= 42)

3 Prune tuples

94 FLOWR Semantics

$x $p $y where

10 1 100 false

9 2 81 false

8 3 64 false$x $p $y where


8 3 64 false

7 4 49 false

6 5 36 true

5 6 25 true

4 7 16 true

3 8 9 true

2 9 4 true

1 10 1 true

$x $p $y where

6 5 36 true

5 6 25 true

4 7 16 true

3 8 9 true

2 9 4 true

1 10 1 true

bull FLWOR populate tuple space lazily (3)4 Evaluate order by clause

5 Normalize order by column evaluate return clause

94 FLOWR Semantics

$x $p $y order by

6 5 36 0

5 6 25 -1

4 7 16 -2 evaluate return clause


4 7 16 -2

3 8 9 -3

2 9 4 -4

1 10 1 -5

$x $p $y position() return

6 5 36 6 (56)

5 6 25 5 (65)

4 7 16 4 (74)

3 8 9 3 (83)

2 9 4 2 (92)

1 10 1 1 (101)

bull Variable bindings Variables are not variablendash Imperative XQuery

ndash Equivalent query

94 FLOWR Semantics

Evaluate the expressionlet $x =

ltxgtltygt12ltygt

ltygt10ltygt

ltygt7ltygt

let $x =

ltxgtltygt12ltygt

ltygt10ltygt

ltygt7ltygt

bull let-bound variables are named values and thus immutablebull Obtain equivalent query via textual replacement (lhs rarrrhs) (Not valid if rhs value depends on a node constructor)


ltygt7ltygt

ltygt13ltygt

ltxgt

let $sum = 0

for $y in $xy

let $sum = $sum + $y

return $sum

ltygt7ltygt

ltygt13ltygt

ltxgt

for $y in $xy

return 0 + $y

91 Introduction

92 Preliminaries


9 XQuery

94 FLWOR Semantics





bull Constructing XML fragmentsndash XQuery expressions may construct nodes with new identity of all 7 node kinds known in XML

bull document nodes elements attributes text nodes comments processing instructions (and namespace nodes)


comments processing instructions (and namespace nodes)

ndash Since item sequences are flat the nested application of node constructors is the only way to hierarchically structure values in XQuery

bull Nested elements may be used to group or compose data andultimately

bull XQuery may be used as an XSLT replacement ie as an XML transformation language


bull Direct node constructors

ndash XQuery node constructors come in two flavors

1 direct constructors and

2 computed constructors



Direct constructorsThe syntax of direct constructors exactly matches the XML syntax any well-formed XML fragment f also is a correct XQuery expression (which when evaluated yields f )

Note Text content and CDATA sections are both mapped into text nodes by the XQuery data model (CDATA isnt remembered)

bull Direct element constructorsndash CDATA isnt remembered

ndash The tag name of a direct constructor is constant its


ltxgtlt[CDATA[foo amp bar]]gtltxgt equiv ltxgtfoo ampamp barltxgtXQuery

ndash The tag name of a direct constructor is constant its content however may be computed by any XQuery expression enclosed in curly braces bullbullbull

bull Computed element content

ndashDouble curly braces ( or ) may be used to create content containing literal curly braces


ltxgt4 max((120)) ltxgt rArrrArrrArrrArr ltxgt42ltxgt

bull Computed element constructors

ndash Definition


In a computed element constructorelement e1 e2

expression e1 (of type string or QName) determines the

element name e determines the sequence of nodes in the


element name e2 determines the sequence of nodes in the elements content

Example computed element name and content

element string-join((foobar)-) 40+2

rArr ltfoo-bargt42ltfoo-bargt

bull Constructing XML Fragments


An application of computed element constructors i18nConsider a dictionary in XML format (bound to variable $dict) with entries

likeltentry word=addressgt

ltvariant lang=degtAdresseltvariantgt

ltvariant lang=itgtindirizzoltvariantgt



ltentrygt

We can use this dictionary to translate the tag name of an XML element $e

into Italian as follows preserving its contents

element

$dictentry[word=name($e)]variant[lang=it]

$e $enode()

bull Direct and computed attribute constructorsndash In direct attribute constructors computed content may be embedded using curly braces


Computed attribute content

ltx a=(42)gt rArrrArrrArrrArr ltx a=4 2gt

ltx a= b=gt rArrrArrrArrrArr ltx b= a=gt

rArrrArrrArrrArr

ndash A computed attribute constructor attribute e1 e2 allows to construct parent-less attributes (impossible in XML) with computed names and content


ltx a= b=gt ltx b= a=gt

ltx a= b=gt rArrrArrrArrrArr ltx a= b=ampquotgt

A computed and re-parented attribute

let $a = attribute a sum((402))

return ltxgt $a ltxgt

bull Text node constructors


Text nodes may be constructed in one of three ways

1 Characters in element content2 via lt[CDATA[bullbullbull]]gt or


2 via lt[CDATA[bullbullbull]]gt or3 using the computed text constructor text e

Content sequence e is atomized to yield a sequence of typeanyAtomicType The atomic values are converted to type string and then concatenated with an intervening ˽If e is () no text node is constructed ndash the constructor yields ()

bull Examples computed text node constructorndash Explicit semantics of text node construction text e


if (empty(e))then ()

else text string-join(for $i in data(e)return string($i)

˽)

ndash Text node construction examples


˽)

text (123) equiv text 1 2 3

let $n = ltxgt

ltygtltzgt

ltxgtname()

return lttgt text $n lttgt

rArrrArrrArrrArr lttgtx y zlttgt

bull XML documents vs fragmentsndash Unlike XML fragments an XML document is rooted in its document

node The difference is observable via XPathbull Remember the (invisible) document root node


doc(xyxml) rArrrArrrArrrArr ltxgtltygtltxgt

ltxgtltygtltxgt rArrrArrrArrrArr ltygt

ltxgt

ltygt

xyxml

ndash A document node may be constructed via document e bull Creating a document node



The context node for the first expression above is the document node for document xyxml

ltygt

ltxgt

(document ltxgtltygtltxgt ) rArrrArrrArrrArr ltxgtltygtltxgt

bull Processing element contentndash The XQuery element constructor is quite flexible the content sequence is not restricted and may have typeitem

ndash Yet the content of an element needs to be of typenode


nodebull Consecutive literal characters yield a single text node containing these characters

bull Expression enclosed in bullbullbull are evaluatedbull Adjacent atomic values are cast to type string and collected in a single text node with intervening ˽

bull A node is copied into the content together with its content All copied nodes receive a new identity

bull Then adjacent text nodes are merged by concatenating their content Text nodes with content are dropped


bull Example processing element contentndash Evaluate the expression below


count(

ltxgtFortytwo40 + 2 foo31415ltygtltzgtltygt

()[1] ltxgtnode())

ndash Solution


The constructed node is

x

text y

z

Fortytwo42foo˽31415

bull Well-formed element contentndash XML fragments constructed by XQuery expressions are subject to the XML rules of well-formedness eg

bull no two attributes of the same element may share a namebull attribute nodes precede any other element content(The content type needs to be a subtype of attribute()(element()|text()|bullbullbull))


(The content type needs to be a subtype of attribute()(element()|text()|bullbullbull))


Violating the well-formedness ruleslet $id = id

return

element x rArrrArrrArrrArr (dynamic error)attribute $id 0

attribute id 1

ltxgtfoo attribute id 0 ltxgt) rArrrArrrArrrArr (type error)

bull Construction generates new node identities

ndash


element x e Deep subtree copy

y y

eequivequivequivequiv

x

notnotnotnotis

ndash Node constructors have side effects


let $e = ltagtltbgtltcgtltygtfooltygtltcgtltagt

let $x = element x $e rArrrArrrArrrArr false()

return exactly-one($ey) is exactly-one($xy)

Observing node identity

let $x = ltxgt

return $x is $x

let $d = doc(uri)

return $d is $drArr rArr rArr rArr true() rArrrArrrArrrArrtrue()

bull Construction establishes document order

ndash Result of the following query


let $x = ltxgt

let $y = ltygt

let $unrelated = ($x $y)

let $related = ltzgt $unrelated ltzgt



return ($unrelated[1] ltlt $unrelated[2]

$related[1] ltlt $related[2] )

Solution

bull Construction pair join partners

ndash A join query


let $a = ltagtltbgtltcgt0ltcgtltbgt

ltbgtltcgt0ltcgtltcgt1ltcgtltcgt2ltcgtltbgt

ltagt

let $x = ltxgtltz id=2gttwoltzgtltz id=0gtzeroltzgt



ltygtltz id=0gtzeroltzgtltz id=3gtthreeltzgtltygt

ltxgt

for $c in $abc

for $z in $xz[id eq $c] ( join predicate )

return ltpairgt $c$ztext() ltpairgt

Result

bull Grouping (attempt 1)ndash A grouping query




ltagt


bull Aggregate functions (sum count ) may be applied to group members ie element mem inside each group



ltxgt

for $c in $abc

return ltgroupgt

$c ltmemgt for $z in $xz[id eq $c]

return $ztext() ltmemgt

ltgroupgt

bull Grouping (attempt 1)

ndash Result (NB group of ltcgt0ltcgt appears twice)


ltgroupgtltcgt0ltcgtltmemgtzerozeroltmemgtltgroupgt


ltgroupgtltcgt1ltcgtltmemgtltgroupgt

ltgroupgtltcgt2ltcgtltmemgttwoltmemgtltgroupgt

larr empty group

ndash Remarksbull The preservation of the empty group for ltcgt1ltcgt

resembles the effect of a relational left outer join

bull The duplicate elimination implicit in $abc is based on node identity but we group by value (id eq $c)

rArr Such groupings call for value-based duplicate elimination




ndash Improved grouping query


let $a = bullbullbullbull bullbullbullbull bullbullbullbull unchanged bullbullbullbull bullbullbullbull bullbullbullbull

let $x = bullbullbullbull bullbullbullbull bullbullbullbull unchanged bullbullbullbull bullbullbullbull bullbullbullbull

for $c in distinct-values($abc)

return ltgroupgt

ndash Notebull Need to rebuild element c ($c bound to values)

bull Inner for loop replaced by equivalent XPath expression


return ltgroupgt

ltcgt $c ltcgt

ltmemgt $xz[id eq $c]text() ltmemgt

ltgroupgt

91 Introduction

92 Preliminaries


9 XQuery

94 FLWOR Semantics





bull XQuery user-defined functionsndash It is typical for non-toy XQuery expressions to contain user-defined functions which encapsulate query details

bull User-defined functions may be collected into modules and then imported by a query

bull Function declarations may be directly embedded into the query


bull Function declarations may be directly embedded into the query prolog (prepended to query separated by )


Declaration of n-ary function f with body e

declare function f ($p1 as t1 $pn as tn) as t0 e

bull If tiis omitted it defaults to item()

bull The pair (f n) is required to be unique (overloading)bull Atomization is applied to the i-th parameter if ti is atomic

bull User-defined function examples


Form textual root-to-node paths

declare default function namespace

httpwww-dbintumdeXQueryfunctions

declare function path($n as node()) as xsstring

fnstring-join(for $a in $nancestor-or-self

ndash May not place user-defd functions in the XQuery builtin function namespace (predefined prefix fn)rArr Use explicit prefix for user-defd or builtin functions

[Gru08]


return fnname($a) )

let $a = ltagtltbgtltcgtltdgtltcgtltdgtltbgtltagt

return $adpath()

rArrrArrrArrrArr (abcdabd)




Reverse a sequence

Reversing a sequence does not inspect the sequences items in any way

declare function reverse($seq)

for $i at $p in $seq

ndash NoteThe calls f() and f(()) invoke different functions

[Gru08]


order by $p descending

return $i

reverse((42altbgtdoc(fooxml)))


bull User-defined functions recursionndash Trees are the prototypical recursive data structure in Computer Science and it is natural to describe computations over trees in a recursive fashion(This is a general and powerful principle in programming derive a functions implementation from the shape of the data it operates over)


[Gru08]

Simulate XPath ancestor via parent axis

declare function ancestors($n as node()) as node()

if (fnempty($n)) then ()

else (ancestors($n) $n)

Questions

1 Will the result be in document order and duplicate free2 What if we declare the parameter type as node()


bull User-defined functions recursion examples


Purpose of function hmm and output of this query

declare function localhmm($e as node()) as xsinteger

if (fnempty($e)) then 1

else fnmax(for $c in $e

return localhmm($c)) + 1

ndash Good stylebull Use predefined namespace local for user-defd functionsbull hmm has a more efficient equivalent (cf a previous slide 16) exploiting the recursion built into axes descendant and ancestor

[Gru08]


localhmm(ltagtltbgt

ltbgtltcgtltdgtfooltdgtltegtltcgtltbgt

ltagt)


bull User-defined functions rename attribute


Rename attribute $from to $todeclare function localxlate($n as node()

$from as xsstring

$to as xsstring)

typeswitch ($n)

case $e as element() return

[Gru08]


let $a = ($e)[name() eq $from]

return

element

node-name($e)

$e( except $a)

if ($a) then attribute $to data($a)

else ()

for $c in $enode()

return localxlate($c $from $to)

default return $n



ndash NB This constructs an entirely new tree

ndash In XQuery 10 there is currently no way to


Invoke xlate

localxlate(ltx id=0 foo=gt

foo

lty zoo=1gtbarltygt

ltxgt

foo

dArrdArrdArrdArr

is currently no way to modify the properties or content of a node

ndash XQuery Update will fill in this gap (work in progress at W3C)

ndash NB XSLT (see above) has been designed to support XMLtransformations like the one exemplified here

[Gru08] XML Databases ndash Silke Eckstein ndash Institut fuumlr Informationssysteme ndash TU Braunschweig 60

foo

bar)

dArrdArrdArrdArr

ltx id=0 bar=gt

foo

lty zoo=1gtbarltygt

ltxgt

bull XQuery the missing piecesndash This chapter did not cover XQuery exhaustively

ndash This course will not cover the following XQuery aspects

bull (namespaces)


bull (namespaces)

bull modules (declaration and import)

bull collations (string equality and comparison)

ndash Reminder XQuery specificationhttpwwww3orgTRxquery(Has become a W3C Recommendation in January 2007)


1 Introduction

2 XML Basics

3 Schema definition

4 XML query languages I

5 Mapping relational data

8 XML query languages II ndashXQuery Data Model

9 XML query languages III ndash XQuery

10XML storage I ndash

97 Overview

uumluumluumluuml

uumluumluumluuml

uumluuml

uumluuml5 Mapping relational data

to XML

6 SQLXML

7 XML processing

10XML storage I ndashOverview

11 XML storage II

12 Updates Transactions

13 Systems

62XML Databases ndash Silke Eckstein ndash Institut fuumlr Informationssysteme ndash TU Braunschweig

uumluumluumluuml

uumluuml

bull Database-Supported XML Processors [Gru08]ndash Th Grust

ndash Lecture Uni Tuumlbingen WS 0809

bull XML and Databases [Scholl07]ndash M Scholl

97 References

ndash M Scholl

ndash Lecture Uni Konstanz WS0708

bull Querying XML ndash XQuery XPath and SQLXML in Contextndash J Melton S Buxton

ndash Morgan KaufmannElsevier 2006 ISBN 978-1558607118


bull XQuery Grundlagen und fortgeschrittene Methoden [LS04]

ndash W Lehner H Schoumlning

ndash dpunktverlag 2004

97 References

bull XML und Datenbanken [KM03]

ndash M Klettke H Meier



bull Now or

bull Room IZ 232

bull Office our Tuesday 1230 ndash 1330 Uhr

Questions Ideas Comments


or on appointment

bull Email ecksteinifiscstu-bsde


91 Introduction

92 Preliminaries


9 XQuery

94 FLWOR Semantics





bull XQuery




91 Introduction









91 Introduction






ndash filtering




91 Introduction




92 Preliminaries







92 Preliminaries












Value comparisons






92 Preliminaries



Surprises




92 Preliminaries














92 Preliminaries

Function Example












92 Preliminaries









91 Introduction

92 Preliminaries



9 XQuery


ndash Where clause

94 FLWOR Semantics











ndash groupings















Iteration examples

for $x in (321)


for $x in (321)


for $x in (321)


2a2b



return ($x$y)


1a1b)

FLWOR Abbreviations

for $v1 in e1return






return e3







A sample csa

b c

d

e g h

f


b

e

c

d

g h

f

1

3 3 3

Answer








return e[$i]

for $i at $p in e


then e[$p]

else ()













for $x in (321)

return ($x)


)



let $x = (321)

return ($x)





then $seq[$p]

else ()





A where clause




for $v in e1where p

return e2

equiv


then e2else ()




a[b = foo]c[2]d[e = 42]

for $a in a



for $a in a

where $ab = foo


where $p = 2


where $de = 42

return $d




In the FLWOR block


In the FLWOR block






for $x at $p in (53142)

order by $p

return $x




for $x at $p in (53142)

order by $p + $x

return $x



for $x at $p in (53142)

order by $x

return $x






ltb id=0gt42ltbgt

ltb id=1gt5ltbgt


ltb id=1gt5ltbgt

ltb id=2gt

ltb id=3gt3ltbgt

ltb id=4gt1ltbgt

ltagt



return $bid

Answer

91 Introduction

92 Preliminaries


9 XQuery

94 FLWOR Semantics






94 FLOWR Semantics









94 FLOWR Semantics


let $y = $x $x

where $y lt= 42

order by 5 - $p

return ($p$x)


10 1 100 false 4 (110)



return ($p$x) 10 1 100 false 4 (110)

9 2 81 false 3 (29)

8 3 64 false 2 (38)

7 4 49 false 1 (47)

6 5 36 true 0 (56)

5 6 25 true -1 (65)

4 7 16 true -2 (74)

3 8 9 true -3 (83)

2 9 4 true -4 (92)

1 10 1 true -5 (101)


94 FLOWR Semantics


10 1 100 false 4 (110)

9 2 81 false 3 (29)

8 3 64 false 2 (38)


8 3 64 false 2 (38)

7 4 49 false 1 (47)

6 5 36 true 0 (56)

5 6 25 true -1 (65)

4 7 16 true -2 (74)

3 8 9 true -3 (83)

2 9 4 true -4 (92)

1 10 1 true -5 (101)


94 FLOWR Semantics


1 10 1 true -5 (101)

2 9 4 true -4 (92)

3 8 9 true -3 (83)


(1019283746556)



3 8 9 true -3 (83)

4 7 16 true -2 (74)

5 6 25 true -1 (65)

6 5 36 true 0 (56)


94 FLOWR Semantics


let $y = $x $x

where $y lt= 42

order by 5 - $p

return ($p$x)

$x $p $y

10 1 100



return ($p$x) 10 1 100

9 2 81

8 3 64

7 4 49

6 5 36

5 6 25

4 7 16

3 8 9

2 9 4

1 10 1


3 Prune tuples

94 FLOWR Semantics

$x $p $y where

10 1 100 false

9 2 81 false



8 3 64 false

7 4 49 false

6 5 36 true

5 6 25 true

4 7 16 true

3 8 9 true

2 9 4 true

1 10 1 true

$x $p $y where

6 5 36 true

5 6 25 true

4 7 16 true

3 8 9 true

2 9 4 true

1 10 1 true



94 FLOWR Semantics

$x $p $y order by

6 5 36 0

5 6 25 -1



4 7 16 -2

3 8 9 -3

2 9 4 -4

1 10 1 -5


6 5 36 6 (56)

5 6 25 5 (65)

4 7 16 4 (74)

3 8 9 3 (83)

2 9 4 2 (92)

1 10 1 1 (101)



94 FLOWR Semantics


ltxgtltygt12ltygt

ltygt10ltygt

ltygt7ltygt

let $x =

ltxgtltygt12ltygt

ltygt10ltygt

ltygt7ltygt



ltygt7ltygt

ltygt13ltygt

ltxgt

let $sum = 0

for $y in $xy


return $sum

ltygt7ltygt

ltygt13ltygt

ltxgt

for $y in $xy

return 0 + $y

91 Introduction

92 Preliminaries


9 XQuery

94 FLWOR Semantics































ndash Definition


















ltentrygt



element


$e $enode()






rArrrArrrArrrArr



















˽)



˽)


let $n = ltxgt

ltygtltzgt

ltxgtname()








ltxgt

ltygt

xyxml





ltygt

ltxgt












count(


()[1] ltxgtnode())

ndash Solution



x

text y

z








return


attribute id 1



ndash



y y


x

notnotnotnotis







let $x = ltxgt

return $x is $x

let $d = doc(uri)





let $x = ltxgt

let $y = ltygt







Solution


ndash A join query




ltagt





ltxgt

for $c in $abc



Result





ltagt





ltxgt

for $c in $abc

return ltgroupgt



ltgroupgt








larr empty group













return ltgroupgt




return ltgroupgt

ltcgt $c ltcgt


ltgroupgt

91 Introduction

92 Preliminaries


9 XQuery

94 FLWOR Semantics























[Gru08]


return fnname($a) )


return $adpath()





Reverse a sequence





[Gru08]



return $i





[Gru08]





Questions











[Gru08]


localhmm(ltagtltbgt


ltagt)





$from as xsstring

$to as xsstring)

typeswitch ($n)


[Gru08]



return

element

node-name($e)

$e( except $a)


else ()

for $c in $enode()


default return $n






Invoke xlate


foo

lty zoo=1gtbarltygt

ltxgt

foo

dArrdArrdArrdArr





foo

bar)

dArrdArrdArrdArr

ltx id=0 bar=gt

foo

lty zoo=1gtbarltygt

ltxgt



bull (namespaces)


bull (namespaces)





1 Introduction

2 XML Basics

3 Schema definition






97 Overview

uumluumluumluuml

uumluumluumluuml

uumluuml


to XML

6 SQLXML

7 XML processing


11 XML storage II


13 Systems


uumluumluumluuml

uumluuml




97 References

ndash M Scholl








97 References





bull Now or

bull Room IZ 232




or on appointment



bull XQuery




91 Introduction









91 Introduction






ndash filtering




91 Introduction




92 Preliminaries







92 Preliminaries












Value comparisons






92 Preliminaries



Surprises




92 Preliminaries














92 Preliminaries

Function Example












92 Preliminaries









91 Introduction

92 Preliminaries



9 XQuery


ndash Where clause

94 FLWOR Semantics











ndash groupings















Iteration examples

for $x in (321)


for $x in (321)


for $x in (321)


2a2b



return ($x$y)


1a1b)

FLWOR Abbreviations

for $v1 in e1return






return e3







A sample csa

b c

d

e g h

f


b

e

c

d

g h

f

1

3 3 3

Answer








return e[$i]

for $i at $p in e


then e[$p]

else ()













for $x in (321)

return ($x)


)



let $x = (321)

return ($x)





then $seq[$p]

else ()





A where clause




for $v in e1where p

return e2

equiv


then e2else ()




a[b = foo]c[2]d[e = 42]

for $a in a



for $a in a

where $ab = foo


where $p = 2


where $de = 42

return $d




In the FLWOR block


In the FLWOR block






for $x at $p in (53142)

order by $p

return $x




for $x at $p in (53142)

order by $p + $x

return $x



for $x at $p in (53142)

order by $x

return $x






ltb id=0gt42ltbgt

ltb id=1gt5ltbgt


ltb id=1gt5ltbgt

ltb id=2gt

ltb id=3gt3ltbgt

ltb id=4gt1ltbgt

ltagt



return $bid

Answer

91 Introduction

92 Preliminaries


9 XQuery

94 FLWOR Semantics






94 FLOWR Semantics









94 FLOWR Semantics


let $y = $x $x

where $y lt= 42

order by 5 - $p

return ($p$x)


10 1 100 false 4 (110)



return ($p$x) 10 1 100 false 4 (110)

9 2 81 false 3 (29)

8 3 64 false 2 (38)

7 4 49 false 1 (47)

6 5 36 true 0 (56)

5 6 25 true -1 (65)

4 7 16 true -2 (74)

3 8 9 true -3 (83)

2 9 4 true -4 (92)

1 10 1 true -5 (101)


94 FLOWR Semantics


10 1 100 false 4 (110)

9 2 81 false 3 (29)

8 3 64 false 2 (38)


8 3 64 false 2 (38)

7 4 49 false 1 (47)

6 5 36 true 0 (56)

5 6 25 true -1 (65)

4 7 16 true -2 (74)

3 8 9 true -3 (83)

2 9 4 true -4 (92)

1 10 1 true -5 (101)


94 FLOWR Semantics


1 10 1 true -5 (101)

2 9 4 true -4 (92)

3 8 9 true -3 (83)


(1019283746556)



3 8 9 true -3 (83)

4 7 16 true -2 (74)

5 6 25 true -1 (65)

6 5 36 true 0 (56)


94 FLOWR Semantics


let $y = $x $x

where $y lt= 42

order by 5 - $p

return ($p$x)

$x $p $y

10 1 100



return ($p$x) 10 1 100

9 2 81

8 3 64

7 4 49

6 5 36

5 6 25

4 7 16

3 8 9

2 9 4

1 10 1


3 Prune tuples

94 FLOWR Semantics

$x $p $y where

10 1 100 false

9 2 81 false



8 3 64 false

7 4 49 false

6 5 36 true

5 6 25 true

4 7 16 true

3 8 9 true

2 9 4 true

1 10 1 true

$x $p $y where

6 5 36 true

5 6 25 true

4 7 16 true

3 8 9 true

2 9 4 true

1 10 1 true



94 FLOWR Semantics

$x $p $y order by

6 5 36 0

5 6 25 -1



4 7 16 -2

3 8 9 -3

2 9 4 -4

1 10 1 -5


6 5 36 6 (56)

5 6 25 5 (65)

4 7 16 4 (74)

3 8 9 3 (83)

2 9 4 2 (92)

1 10 1 1 (101)



94 FLOWR Semantics


ltxgtltygt12ltygt

ltygt10ltygt

ltygt7ltygt

let $x =

ltxgtltygt12ltygt

ltygt10ltygt

ltygt7ltygt



ltygt7ltygt

ltygt13ltygt

ltxgt

let $sum = 0

for $y in $xy


return $sum

ltygt7ltygt

ltygt13ltygt

ltxgt

for $y in $xy

return 0 + $y

91 Introduction

92 Preliminaries


9 XQuery

94 FLWOR Semantics































ndash Definition


















ltentrygt



element


$e $enode()






rArrrArrrArrrArr



















˽)



˽)


let $n = ltxgt

ltygtltzgt

ltxgtname()








ltxgt

ltygt

xyxml





ltygt

ltxgt












count(


()[1] ltxgtnode())

ndash Solution



x

text y

z








return


attribute id 1



ndash



y y


x

notnotnotnotis







let $x = ltxgt

return $x is $x

let $d = doc(uri)





let $x = ltxgt

let $y = ltygt







Solution


ndash A join query




ltagt





ltxgt

for $c in $abc



Result





ltagt





ltxgt

for $c in $abc

return ltgroupgt



ltgroupgt








larr empty group













return ltgroupgt




return ltgroupgt

ltcgt $c ltcgt


ltgroupgt

91 Introduction

92 Preliminaries


9 XQuery

94 FLWOR Semantics























[Gru08]


return fnname($a) )


return $adpath()





Reverse a sequence





[Gru08]



return $i





[Gru08]





Questions











[Gru08]


localhmm(ltagtltbgt


ltagt)





$from as xsstring

$to as xsstring)

typeswitch ($n)


[Gru08]



return

element

node-name($e)

$e( except $a)


else ()

for $c in $enode()


default return $n






Invoke xlate


foo

lty zoo=1gtbarltygt

ltxgt

foo

dArrdArrdArrdArr





foo

bar)

dArrdArrdArrdArr

ltx id=0 bar=gt

foo

lty zoo=1gtbarltygt

ltxgt



bull (namespaces)


bull (namespaces)





1 Introduction

2 XML Basics

3 Schema definition






97 Overview

uumluumluumluuml

uumluumluumluuml

uumluuml


to XML

6 SQLXML

7 XML processing


11 XML storage II


13 Systems


uumluumluumluuml

uumluuml




97 References

ndash M Scholl








97 References





bull Now or

bull Room IZ 232




or on appointment






91 Introduction






ndash filtering




91 Introduction




92 Preliminaries







92 Preliminaries












Value comparisons






92 Preliminaries



Surprises




92 Preliminaries














92 Preliminaries

Function Example












92 Preliminaries









91 Introduction

92 Preliminaries



9 XQuery


ndash Where clause

94 FLWOR Semantics











ndash groupings















Iteration examples

for $x in (321)


for $x in (321)


for $x in (321)


2a2b



return ($x$y)


1a1b)

FLWOR Abbreviations

for $v1 in e1return






return e3







A sample csa

b c

d

e g h

f


b

e

c

d

g h

f

1

3 3 3

Answer








return e[$i]

for $i at $p in e


then e[$p]

else ()













for $x in (321)

return ($x)


)



let $x = (321)

return ($x)





then $seq[$p]

else ()





A where clause




for $v in e1where p

return e2

equiv


then e2else ()




a[b = foo]c[2]d[e = 42]

for $a in a



for $a in a

where $ab = foo


where $p = 2


where $de = 42

return $d




In the FLWOR block


In the FLWOR block






for $x at $p in (53142)

order by $p

return $x




for $x at $p in (53142)

order by $p + $x

return $x



for $x at $p in (53142)

order by $x

return $x






ltb id=0gt42ltbgt

ltb id=1gt5ltbgt


ltb id=1gt5ltbgt

ltb id=2gt

ltb id=3gt3ltbgt

ltb id=4gt1ltbgt

ltagt



return $bid

Answer

91 Introduction

92 Preliminaries


9 XQuery

94 FLWOR Semantics






94 FLOWR Semantics









94 FLOWR Semantics


let $y = $x $x

where $y lt= 42

order by 5 - $p

return ($p$x)


10 1 100 false 4 (110)



return ($p$x) 10 1 100 false 4 (110)

9 2 81 false 3 (29)

8 3 64 false 2 (38)

7 4 49 false 1 (47)

6 5 36 true 0 (56)

5 6 25 true -1 (65)

4 7 16 true -2 (74)

3 8 9 true -3 (83)

2 9 4 true -4 (92)

1 10 1 true -5 (101)


94 FLOWR Semantics


10 1 100 false 4 (110)

9 2 81 false 3 (29)

8 3 64 false 2 (38)


8 3 64 false 2 (38)

7 4 49 false 1 (47)

6 5 36 true 0 (56)

5 6 25 true -1 (65)

4 7 16 true -2 (74)

3 8 9 true -3 (83)

2 9 4 true -4 (92)

1 10 1 true -5 (101)


94 FLOWR Semantics


1 10 1 true -5 (101)

2 9 4 true -4 (92)

3 8 9 true -3 (83)


(1019283746556)



3 8 9 true -3 (83)

4 7 16 true -2 (74)

5 6 25 true -1 (65)

6 5 36 true 0 (56)


94 FLOWR Semantics


let $y = $x $x

where $y lt= 42

order by 5 - $p

return ($p$x)

$x $p $y

10 1 100



return ($p$x) 10 1 100

9 2 81

8 3 64

7 4 49

6 5 36

5 6 25

4 7 16

3 8 9

2 9 4

1 10 1


3 Prune tuples

94 FLOWR Semantics

$x $p $y where

10 1 100 false

9 2 81 false



8 3 64 false

7 4 49 false

6 5 36 true

5 6 25 true

4 7 16 true

3 8 9 true

2 9 4 true

1 10 1 true

$x $p $y where

6 5 36 true

5 6 25 true

4 7 16 true

3 8 9 true

2 9 4 true

1 10 1 true



94 FLOWR Semantics

$x $p $y order by

6 5 36 0

5 6 25 -1



4 7 16 -2

3 8 9 -3

2 9 4 -4

1 10 1 -5


6 5 36 6 (56)

5 6 25 5 (65)

4 7 16 4 (74)

3 8 9 3 (83)

2 9 4 2 (92)

1 10 1 1 (101)



94 FLOWR Semantics


ltxgtltygt12ltygt

ltygt10ltygt

ltygt7ltygt

let $x =

ltxgtltygt12ltygt

ltygt10ltygt

ltygt7ltygt



ltygt7ltygt

ltygt13ltygt

ltxgt

let $sum = 0

for $y in $xy


return $sum

ltygt7ltygt

ltygt13ltygt

ltxgt

for $y in $xy

return 0 + $y

91 Introduction

92 Preliminaries


9 XQuery

94 FLWOR Semantics































ndash Definition


















ltentrygt



element


$e $enode()






rArrrArrrArrrArr



















˽)



˽)


let $n = ltxgt

ltygtltzgt

ltxgtname()








ltxgt

ltygt

xyxml





ltygt

ltxgt












count(


()[1] ltxgtnode())

ndash Solution



x

text y

z








return


attribute id 1



ndash



y y


x

notnotnotnotis







let $x = ltxgt

return $x is $x

let $d = doc(uri)





let $x = ltxgt

let $y = ltygt







Solution


ndash A join query




ltagt





ltxgt

for $c in $abc



Result





ltagt





ltxgt

for $c in $abc

return ltgroupgt



ltgroupgt








larr empty group













return ltgroupgt




return ltgroupgt

ltcgt $c ltcgt


ltgroupgt

91 Introduction

92 Preliminaries


9 XQuery

94 FLWOR Semantics























[Gru08]


return fnname($a) )


return $adpath()





Reverse a sequence





[Gru08]



return $i





[Gru08]





Questions











[Gru08]


localhmm(ltagtltbgt


ltagt)





$from as xsstring

$to as xsstring)

typeswitch ($n)


[Gru08]



return

element

node-name($e)

$e( except $a)


else ()

for $c in $enode()


default return $n






Invoke xlate


foo

lty zoo=1gtbarltygt

ltxgt

foo

dArrdArrdArrdArr





foo

bar)

dArrdArrdArrdArr

ltx id=0 bar=gt

foo

lty zoo=1gtbarltygt

ltxgt



bull (namespaces)


bull (namespaces)





1 Introduction

2 XML Basics

3 Schema definition






97 Overview

uumluumluumluuml

uumluumluumluuml

uumluuml


to XML

6 SQLXML

7 XML processing


11 XML storage II


13 Systems


uumluumluumluuml

uumluuml




97 References

ndash M Scholl








97 References





bull Now or

bull Room IZ 232




or on appointment




91 Introduction




92 Preliminaries







92 Preliminaries












Value comparisons






92 Preliminaries



Surprises




92 Preliminaries














92 Preliminaries

Function Example












92 Preliminaries









91 Introduction

92 Preliminaries



9 XQuery


ndash Where clause

94 FLWOR Semantics











ndash groupings















Iteration examples

for $x in (321)


for $x in (321)


for $x in (321)


2a2b



return ($x$y)


1a1b)

FLWOR Abbreviations

for $v1 in e1return






return e3







A sample csa

b c

d

e g h

f


b

e

c

d

g h

f

1

3 3 3

Answer








return e[$i]

for $i at $p in e


then e[$p]

else ()













for $x in (321)

return ($x)


)



let $x = (321)

return ($x)





then $seq[$p]

else ()





A where clause




for $v in e1where p

return e2

equiv


then e2else ()




a[b = foo]c[2]d[e = 42]

for $a in a



for $a in a

where $ab = foo


where $p = 2


where $de = 42

return $d




In the FLWOR block


In the FLWOR block






for $x at $p in (53142)

order by $p

return $x




for $x at $p in (53142)

order by $p + $x

return $x



for $x at $p in (53142)

order by $x

return $x






ltb id=0gt42ltbgt

ltb id=1gt5ltbgt


ltb id=1gt5ltbgt

ltb id=2gt

ltb id=3gt3ltbgt

ltb id=4gt1ltbgt

ltagt



return $bid

Answer

91 Introduction

92 Preliminaries


9 XQuery

94 FLWOR Semantics






94 FLOWR Semantics









94 FLOWR Semantics


let $y = $x $x

where $y lt= 42

order by 5 - $p

return ($p$x)


10 1 100 false 4 (110)



return ($p$x) 10 1 100 false 4 (110)

9 2 81 false 3 (29)

8 3 64 false 2 (38)

7 4 49 false 1 (47)

6 5 36 true 0 (56)

5 6 25 true -1 (65)

4 7 16 true -2 (74)

3 8 9 true -3 (83)

2 9 4 true -4 (92)

1 10 1 true -5 (101)


94 FLOWR Semantics


10 1 100 false 4 (110)

9 2 81 false 3 (29)

8 3 64 false 2 (38)


8 3 64 false 2 (38)

7 4 49 false 1 (47)

6 5 36 true 0 (56)

5 6 25 true -1 (65)

4 7 16 true -2 (74)

3 8 9 true -3 (83)

2 9 4 true -4 (92)

1 10 1 true -5 (101)


94 FLOWR Semantics


1 10 1 true -5 (101)

2 9 4 true -4 (92)

3 8 9 true -3 (83)


(1019283746556)



3 8 9 true -3 (83)

4 7 16 true -2 (74)

5 6 25 true -1 (65)

6 5 36 true 0 (56)


94 FLOWR Semantics


let $y = $x $x

where $y lt= 42

order by 5 - $p

return ($p$x)

$x $p $y

10 1 100



return ($p$x) 10 1 100

9 2 81

8 3 64

7 4 49

6 5 36

5 6 25

4 7 16

3 8 9

2 9 4

1 10 1


3 Prune tuples

94 FLOWR Semantics

$x $p $y where

10 1 100 false

9 2 81 false



8 3 64 false

7 4 49 false

6 5 36 true

5 6 25 true

4 7 16 true

3 8 9 true

2 9 4 true

1 10 1 true

$x $p $y where

6 5 36 true

5 6 25 true

4 7 16 true

3 8 9 true

2 9 4 true

1 10 1 true



94 FLOWR Semantics

$x $p $y order by

6 5 36 0

5 6 25 -1



4 7 16 -2

3 8 9 -3

2 9 4 -4

1 10 1 -5


6 5 36 6 (56)

5 6 25 5 (65)

4 7 16 4 (74)

3 8 9 3 (83)

2 9 4 2 (92)

1 10 1 1 (101)



94 FLOWR Semantics


ltxgtltygt12ltygt

ltygt10ltygt

ltygt7ltygt

let $x =

ltxgtltygt12ltygt

ltygt10ltygt

ltygt7ltygt



ltygt7ltygt

ltygt13ltygt

ltxgt

let $sum = 0

for $y in $xy


return $sum

ltygt7ltygt

ltygt13ltygt

ltxgt

for $y in $xy

return 0 + $y

91 Introduction

92 Preliminaries


9 XQuery

94 FLWOR Semantics































ndash Definition


















ltentrygt



element


$e $enode()






rArrrArrrArrrArr



















˽)



˽)


let $n = ltxgt

ltygtltzgt

ltxgtname()








ltxgt

ltygt

xyxml





ltygt

ltxgt












count(


()[1] ltxgtnode())

ndash Solution



x

text y

z








return


attribute id 1



ndash



y y


x

notnotnotnotis







let $x = ltxgt

return $x is $x

let $d = doc(uri)





let $x = ltxgt

let $y = ltygt







Solution


ndash A join query




ltagt





ltxgt

for $c in $abc



Result





ltagt





ltxgt

for $c in $abc

return ltgroupgt



ltgroupgt








larr empty group













return ltgroupgt




return ltgroupgt

ltcgt $c ltcgt


ltgroupgt

91 Introduction

92 Preliminaries


9 XQuery

94 FLWOR Semantics























[Gru08]


return fnname($a) )


return $adpath()





Reverse a sequence





[Gru08]



return $i





[Gru08]





Questions











[Gru08]


localhmm(ltagtltbgt


ltagt)





$from as xsstring

$to as xsstring)

typeswitch ($n)


[Gru08]



return

element

node-name($e)

$e( except $a)


else ()

for $c in $enode()


default return $n






Invoke xlate


foo

lty zoo=1gtbarltygt

ltxgt

foo

dArrdArrdArrdArr





foo

bar)

dArrdArrdArrdArr

ltx id=0 bar=gt

foo

lty zoo=1gtbarltygt

ltxgt



bull (namespaces)


bull (namespaces)





1 Introduction

2 XML Basics

3 Schema definition






97 Overview

uumluumluumluuml

uumluumluumluuml

uumluuml


to XML

6 SQLXML

7 XML processing


11 XML storage II


13 Systems


uumluumluumluuml

uumluuml




97 References

ndash M Scholl








97 References





bull Now or

bull Room IZ 232




or on appointment





92 Preliminaries







92 Preliminaries












Value comparisons






92 Preliminaries



Surprises




92 Preliminaries














92 Preliminaries

Function Example












92 Preliminaries









91 Introduction

92 Preliminaries



9 XQuery


ndash Where clause

94 FLWOR Semantics











ndash groupings















Iteration examples

for $x in (321)


for $x in (321)


for $x in (321)


2a2b



return ($x$y)


1a1b)

FLWOR Abbreviations

for $v1 in e1return






return e3







A sample csa

b c

d

e g h

f


b

e

c

d

g h

f

1

3 3 3

Answer








return e[$i]

for $i at $p in e


then e[$p]

else ()













for $x in (321)

return ($x)


)



let $x = (321)

return ($x)





then $seq[$p]

else ()





A where clause




for $v in e1where p

return e2

equiv


then e2else ()




a[b = foo]c[2]d[e = 42]

for $a in a



for $a in a

where $ab = foo


where $p = 2


where $de = 42

return $d




In the FLWOR block


In the FLWOR block






for $x at $p in (53142)

order by $p

return $x




for $x at $p in (53142)

order by $p + $x

return $x



for $x at $p in (53142)

order by $x

return $x






ltb id=0gt42ltbgt

ltb id=1gt5ltbgt


ltb id=1gt5ltbgt

ltb id=2gt

ltb id=3gt3ltbgt

ltb id=4gt1ltbgt

ltagt



return $bid

Answer

91 Introduction

92 Preliminaries


9 XQuery

94 FLWOR Semantics






94 FLOWR Semantics









94 FLOWR Semantics


let $y = $x $x

where $y lt= 42

order by 5 - $p

return ($p$x)


10 1 100 false 4 (110)



return ($p$x) 10 1 100 false 4 (110)

9 2 81 false 3 (29)

8 3 64 false 2 (38)

7 4 49 false 1 (47)

6 5 36 true 0 (56)

5 6 25 true -1 (65)

4 7 16 true -2 (74)

3 8 9 true -3 (83)

2 9 4 true -4 (92)

1 10 1 true -5 (101)


94 FLOWR Semantics


10 1 100 false 4 (110)

9 2 81 false 3 (29)

8 3 64 false 2 (38)


8 3 64 false 2 (38)

7 4 49 false 1 (47)

6 5 36 true 0 (56)

5 6 25 true -1 (65)

4 7 16 true -2 (74)

3 8 9 true -3 (83)

2 9 4 true -4 (92)

1 10 1 true -5 (101)


94 FLOWR Semantics


1 10 1 true -5 (101)

2 9 4 true -4 (92)

3 8 9 true -3 (83)


(1019283746556)



3 8 9 true -3 (83)

4 7 16 true -2 (74)

5 6 25 true -1 (65)

6 5 36 true 0 (56)


94 FLOWR Semantics


let $y = $x $x

where $y lt= 42

order by 5 - $p

return ($p$x)

$x $p $y

10 1 100



return ($p$x) 10 1 100

9 2 81

8 3 64

7 4 49

6 5 36

5 6 25

4 7 16

3 8 9

2 9 4

1 10 1


3 Prune tuples

94 FLOWR Semantics

$x $p $y where

10 1 100 false

9 2 81 false



8 3 64 false

7 4 49 false

6 5 36 true

5 6 25 true

4 7 16 true

3 8 9 true

2 9 4 true

1 10 1 true

$x $p $y where

6 5 36 true

5 6 25 true

4 7 16 true

3 8 9 true

2 9 4 true

1 10 1 true



94 FLOWR Semantics

$x $p $y order by

6 5 36 0

5 6 25 -1



4 7 16 -2

3 8 9 -3

2 9 4 -4

1 10 1 -5


6 5 36 6 (56)

5 6 25 5 (65)

4 7 16 4 (74)

3 8 9 3 (83)

2 9 4 2 (92)

1 10 1 1 (101)



94 FLOWR Semantics


ltxgtltygt12ltygt

ltygt10ltygt

ltygt7ltygt

let $x =

ltxgtltygt12ltygt

ltygt10ltygt

ltygt7ltygt



ltygt7ltygt

ltygt13ltygt

ltxgt

let $sum = 0

for $y in $xy


return $sum

ltygt7ltygt

ltygt13ltygt

ltxgt

for $y in $xy

return 0 + $y

91 Introduction

92 Preliminaries


9 XQuery

94 FLWOR Semantics































ndash Definition


















ltentrygt



element


$e $enode()






rArrrArrrArrrArr



















˽)



˽)


let $n = ltxgt

ltygtltzgt

ltxgtname()








ltxgt

ltygt

xyxml





ltygt

ltxgt












count(


()[1] ltxgtnode())

ndash Solution



x

text y

z








return


attribute id 1



ndash



y y


x

notnotnotnotis







let $x = ltxgt

return $x is $x

let $d = doc(uri)





let $x = ltxgt

let $y = ltygt







Solution


ndash A join query




ltagt





ltxgt

for $c in $abc



Result





ltagt





ltxgt

for $c in $abc

return ltgroupgt



ltgroupgt








larr empty group













return ltgroupgt




return ltgroupgt

ltcgt $c ltcgt


ltgroupgt

91 Introduction

92 Preliminaries


9 XQuery

94 FLWOR Semantics























[Gru08]


return fnname($a) )


return $adpath()





Reverse a sequence





[Gru08]



return $i





[Gru08]





Questions











[Gru08]


localhmm(ltagtltbgt


ltagt)





$from as xsstring

$to as xsstring)

typeswitch ($n)


[Gru08]



return

element

node-name($e)

$e( except $a)


else ()

for $c in $enode()


default return $n






Invoke xlate


foo

lty zoo=1gtbarltygt

ltxgt

foo

dArrdArrdArrdArr





foo

bar)

dArrdArrdArrdArr

ltx id=0 bar=gt

foo

lty zoo=1gtbarltygt

ltxgt



bull (namespaces)


bull (namespaces)





1 Introduction

2 XML Basics

3 Schema definition






97 Overview

uumluumluumluuml

uumluumluumluuml

uumluuml


to XML

6 SQLXML

7 XML processing


11 XML storage II


13 Systems


uumluumluumluuml

uumluuml




97 References

ndash M Scholl








97 References





bull Now or

bull Room IZ 232




or on appointment



92 Preliminaries












Value comparisons






92 Preliminaries



Surprises




92 Preliminaries














92 Preliminaries

Function Example












92 Preliminaries









91 Introduction

92 Preliminaries



9 XQuery


ndash Where clause

94 FLWOR Semantics











ndash groupings















Iteration examples

for $x in (321)


for $x in (321)


for $x in (321)


2a2b



return ($x$y)


1a1b)

FLWOR Abbreviations

for $v1 in e1return






return e3







A sample csa

b c

d

e g h

f


b

e

c

d

g h

f

1

3 3 3

Answer








return e[$i]

for $i at $p in e


then e[$p]

else ()













for $x in (321)

return ($x)


)



let $x = (321)

return ($x)





then $seq[$p]

else ()





A where clause




for $v in e1where p

return e2

equiv


then e2else ()




a[b = foo]c[2]d[e = 42]

for $a in a



for $a in a

where $ab = foo


where $p = 2


where $de = 42

return $d




In the FLWOR block


In the FLWOR block






for $x at $p in (53142)

order by $p

return $x




for $x at $p in (53142)

order by $p + $x

return $x



for $x at $p in (53142)

order by $x

return $x






ltb id=0gt42ltbgt

ltb id=1gt5ltbgt


ltb id=1gt5ltbgt

ltb id=2gt

ltb id=3gt3ltbgt

ltb id=4gt1ltbgt

ltagt



return $bid

Answer

91 Introduction

92 Preliminaries


9 XQuery

94 FLWOR Semantics






94 FLOWR Semantics









94 FLOWR Semantics


let $y = $x $x

where $y lt= 42

order by 5 - $p

return ($p$x)


10 1 100 false 4 (110)



return ($p$x) 10 1 100 false 4 (110)

9 2 81 false 3 (29)

8 3 64 false 2 (38)

7 4 49 false 1 (47)

6 5 36 true 0 (56)

5 6 25 true -1 (65)

4 7 16 true -2 (74)

3 8 9 true -3 (83)

2 9 4 true -4 (92)

1 10 1 true -5 (101)


94 FLOWR Semantics


10 1 100 false 4 (110)

9 2 81 false 3 (29)

8 3 64 false 2 (38)


8 3 64 false 2 (38)

7 4 49 false 1 (47)

6 5 36 true 0 (56)

5 6 25 true -1 (65)

4 7 16 true -2 (74)

3 8 9 true -3 (83)

2 9 4 true -4 (92)

1 10 1 true -5 (101)


94 FLOWR Semantics


1 10 1 true -5 (101)

2 9 4 true -4 (92)

3 8 9 true -3 (83)


(1019283746556)



3 8 9 true -3 (83)

4 7 16 true -2 (74)

5 6 25 true -1 (65)

6 5 36 true 0 (56)


94 FLOWR Semantics


let $y = $x $x

where $y lt= 42

order by 5 - $p

return ($p$x)

$x $p $y

10 1 100



return ($p$x) 10 1 100

9 2 81

8 3 64

7 4 49

6 5 36

5 6 25

4 7 16

3 8 9

2 9 4

1 10 1


3 Prune tuples

94 FLOWR Semantics

$x $p $y where

10 1 100 false

9 2 81 false



8 3 64 false

7 4 49 false

6 5 36 true

5 6 25 true

4 7 16 true

3 8 9 true

2 9 4 true

1 10 1 true

$x $p $y where

6 5 36 true

5 6 25 true

4 7 16 true

3 8 9 true

2 9 4 true

1 10 1 true



94 FLOWR Semantics

$x $p $y order by

6 5 36 0

5 6 25 -1



4 7 16 -2

3 8 9 -3

2 9 4 -4

1 10 1 -5


6 5 36 6 (56)

5 6 25 5 (65)

4 7 16 4 (74)

3 8 9 3 (83)

2 9 4 2 (92)

1 10 1 1 (101)



94 FLOWR Semantics


ltxgtltygt12ltygt

ltygt10ltygt

ltygt7ltygt

let $x =

ltxgtltygt12ltygt

ltygt10ltygt

ltygt7ltygt



ltygt7ltygt

ltygt13ltygt

ltxgt

let $sum = 0

for $y in $xy


return $sum

ltygt7ltygt

ltygt13ltygt

ltxgt

for $y in $xy

return 0 + $y

91 Introduction

92 Preliminaries


9 XQuery

94 FLWOR Semantics































ndash Definition


















ltentrygt



element


$e $enode()






rArrrArrrArrrArr



















˽)



˽)


let $n = ltxgt

ltygtltzgt

ltxgtname()








ltxgt

ltygt

xyxml





ltygt

ltxgt












count(


()[1] ltxgtnode())

ndash Solution



x

text y

z








return


attribute id 1



ndash



y y


x

notnotnotnotis







let $x = ltxgt

return $x is $x

let $d = doc(uri)





let $x = ltxgt

let $y = ltygt







Solution


ndash A join query




ltagt





ltxgt

for $c in $abc



Result





ltagt





ltxgt

for $c in $abc

return ltgroupgt



ltgroupgt








larr empty group













return ltgroupgt




return ltgroupgt

ltcgt $c ltcgt


ltgroupgt

91 Introduction

92 Preliminaries


9 XQuery

94 FLWOR Semantics























[Gru08]


return fnname($a) )


return $adpath()





Reverse a sequence





[Gru08]



return $i





[Gru08]





Questions











[Gru08]


localhmm(ltagtltbgt


ltagt)





$from as xsstring

$to as xsstring)

typeswitch ($n)


[Gru08]



return

element

node-name($e)

$e( except $a)


else ()

for $c in $enode()


default return $n






Invoke xlate


foo

lty zoo=1gtbarltygt

ltxgt

foo

dArrdArrdArrdArr





foo

bar)

dArrdArrdArrdArr

ltx id=0 bar=gt

foo

lty zoo=1gtbarltygt

ltxgt



bull (namespaces)


bull (namespaces)





1 Introduction

2 XML Basics

3 Schema definition






97 Overview

uumluumluumluuml

uumluumluumluuml

uumluuml


to XML

6 SQLXML

7 XML processing


11 XML storage II


13 Systems


uumluumluumluuml

uumluuml




97 References

ndash M Scholl








97 References





bull Now or

bull Room IZ 232




or on appointment





92 Preliminaries



Surprises




92 Preliminaries














92 Preliminaries

Function Example












92 Preliminaries









91 Introduction

92 Preliminaries



9 XQuery


ndash Where clause

94 FLWOR Semantics











ndash groupings















Iteration examples

for $x in (321)


for $x in (321)


for $x in (321)


2a2b



return ($x$y)


1a1b)

FLWOR Abbreviations

for $v1 in e1return






return e3







A sample csa

b c

d

e g h

f


b

e

c

d

g h

f

1

3 3 3

Answer








return e[$i]

for $i at $p in e


then e[$p]

else ()













for $x in (321)

return ($x)


)



let $x = (321)

return ($x)





then $seq[$p]

else ()





A where clause




for $v in e1where p

return e2

equiv


then e2else ()




a[b = foo]c[2]d[e = 42]

for $a in a



for $a in a

where $ab = foo


where $p = 2


where $de = 42

return $d




In the FLWOR block


In the FLWOR block






for $x at $p in (53142)

order by $p

return $x




for $x at $p in (53142)

order by $p + $x

return $x



for $x at $p in (53142)

order by $x

return $x






ltb id=0gt42ltbgt

ltb id=1gt5ltbgt


ltb id=1gt5ltbgt

ltb id=2gt

ltb id=3gt3ltbgt

ltb id=4gt1ltbgt

ltagt



return $bid

Answer

91 Introduction

92 Preliminaries


9 XQuery

94 FLWOR Semantics






94 FLOWR Semantics









94 FLOWR Semantics


let $y = $x $x

where $y lt= 42

order by 5 - $p

return ($p$x)


10 1 100 false 4 (110)



return ($p$x) 10 1 100 false 4 (110)

9 2 81 false 3 (29)

8 3 64 false 2 (38)

7 4 49 false 1 (47)

6 5 36 true 0 (56)

5 6 25 true -1 (65)

4 7 16 true -2 (74)

3 8 9 true -3 (83)

2 9 4 true -4 (92)

1 10 1 true -5 (101)


94 FLOWR Semantics


10 1 100 false 4 (110)

9 2 81 false 3 (29)

8 3 64 false 2 (38)


8 3 64 false 2 (38)

7 4 49 false 1 (47)

6 5 36 true 0 (56)

5 6 25 true -1 (65)

4 7 16 true -2 (74)

3 8 9 true -3 (83)

2 9 4 true -4 (92)

1 10 1 true -5 (101)


94 FLOWR Semantics


1 10 1 true -5 (101)

2 9 4 true -4 (92)

3 8 9 true -3 (83)


(1019283746556)



3 8 9 true -3 (83)

4 7 16 true -2 (74)

5 6 25 true -1 (65)

6 5 36 true 0 (56)


94 FLOWR Semantics


let $y = $x $x

where $y lt= 42

order by 5 - $p

return ($p$x)

$x $p $y

10 1 100



return ($p$x) 10 1 100

9 2 81

8 3 64

7 4 49

6 5 36

5 6 25

4 7 16

3 8 9

2 9 4

1 10 1


3 Prune tuples

94 FLOWR Semantics

$x $p $y where

10 1 100 false

9 2 81 false



8 3 64 false

7 4 49 false

6 5 36 true

5 6 25 true

4 7 16 true

3 8 9 true

2 9 4 true

1 10 1 true

$x $p $y where

6 5 36 true

5 6 25 true

4 7 16 true

3 8 9 true

2 9 4 true

1 10 1 true



94 FLOWR Semantics

$x $p $y order by

6 5 36 0

5 6 25 -1



4 7 16 -2

3 8 9 -3

2 9 4 -4

1 10 1 -5


6 5 36 6 (56)

5 6 25 5 (65)

4 7 16 4 (74)

3 8 9 3 (83)

2 9 4 2 (92)

1 10 1 1 (101)



94 FLOWR Semantics


ltxgtltygt12ltygt

ltygt10ltygt

ltygt7ltygt

let $x =

ltxgtltygt12ltygt

ltygt10ltygt

ltygt7ltygt



ltygt7ltygt

ltygt13ltygt

ltxgt

let $sum = 0

for $y in $xy


return $sum

ltygt7ltygt

ltygt13ltygt

ltxgt

for $y in $xy

return 0 + $y

91 Introduction

92 Preliminaries


9 XQuery

94 FLWOR Semantics































ndash Definition


















ltentrygt



element


$e $enode()






rArrrArrrArrrArr



















˽)



˽)


let $n = ltxgt

ltygtltzgt

ltxgtname()








ltxgt

ltygt

xyxml





ltygt

ltxgt












count(


()[1] ltxgtnode())

ndash Solution



x

text y

z








return


attribute id 1



ndash



y y


x

notnotnotnotis







let $x = ltxgt

return $x is $x

let $d = doc(uri)





let $x = ltxgt

let $y = ltygt







Solution


ndash A join query




ltagt





ltxgt

for $c in $abc



Result





ltagt





ltxgt

for $c in $abc

return ltgroupgt



ltgroupgt








larr empty group













return ltgroupgt




return ltgroupgt

ltcgt $c ltcgt


ltgroupgt

91 Introduction

92 Preliminaries


9 XQuery

94 FLWOR Semantics























[Gru08]


return fnname($a) )


return $adpath()





Reverse a sequence





[Gru08]



return $i





[Gru08]





Questions











[Gru08]


localhmm(ltagtltbgt


ltagt)





$from as xsstring

$to as xsstring)

typeswitch ($n)


[Gru08]



return

element

node-name($e)

$e( except $a)


else ()

for $c in $enode()


default return $n






Invoke xlate


foo

lty zoo=1gtbarltygt

ltxgt

foo

dArrdArrdArrdArr





foo

bar)

dArrdArrdArrdArr

ltx id=0 bar=gt

foo

lty zoo=1gtbarltygt

ltxgt



bull (namespaces)


bull (namespaces)





1 Introduction

2 XML Basics

3 Schema definition






97 Overview

uumluumluumluuml

uumluumluumluuml

uumluuml


to XML

6 SQLXML

7 XML processing


11 XML storage II


13 Systems


uumluumluumluuml

uumluuml




97 References

ndash M Scholl








97 References





bull Now or

bull Room IZ 232




or on appointment




92 Preliminaries














92 Preliminaries

Function Example












92 Preliminaries









91 Introduction

92 Preliminaries



9 XQuery


ndash Where clause

94 FLWOR Semantics











ndash groupings















Iteration examples

for $x in (321)


for $x in (321)


for $x in (321)


2a2b



return ($x$y)


1a1b)

FLWOR Abbreviations

for $v1 in e1return






return e3







A sample csa

b c

d

e g h

f


b

e

c

d

g h

f

1

3 3 3

Answer








return e[$i]

for $i at $p in e


then e[$p]

else ()













for $x in (321)

return ($x)


)



let $x = (321)

return ($x)





then $seq[$p]

else ()





A where clause




for $v in e1where p

return e2

equiv


then e2else ()




a[b = foo]c[2]d[e = 42]

for $a in a



for $a in a

where $ab = foo


where $p = 2


where $de = 42

return $d




In the FLWOR block


In the FLWOR block






for $x at $p in (53142)

order by $p

return $x




for $x at $p in (53142)

order by $p + $x

return $x



for $x at $p in (53142)

order by $x

return $x






ltb id=0gt42ltbgt

ltb id=1gt5ltbgt


ltb id=1gt5ltbgt

ltb id=2gt

ltb id=3gt3ltbgt

ltb id=4gt1ltbgt

ltagt



return $bid

Answer

91 Introduction

92 Preliminaries


9 XQuery

94 FLWOR Semantics






94 FLOWR Semantics









94 FLOWR Semantics


let $y = $x $x

where $y lt= 42

order by 5 - $p

return ($p$x)


10 1 100 false 4 (110)



return ($p$x) 10 1 100 false 4 (110)

9 2 81 false 3 (29)

8 3 64 false 2 (38)

7 4 49 false 1 (47)

6 5 36 true 0 (56)

5 6 25 true -1 (65)

4 7 16 true -2 (74)

3 8 9 true -3 (83)

2 9 4 true -4 (92)

1 10 1 true -5 (101)


94 FLOWR Semantics


10 1 100 false 4 (110)

9 2 81 false 3 (29)

8 3 64 false 2 (38)


8 3 64 false 2 (38)

7 4 49 false 1 (47)

6 5 36 true 0 (56)

5 6 25 true -1 (65)

4 7 16 true -2 (74)

3 8 9 true -3 (83)

2 9 4 true -4 (92)

1 10 1 true -5 (101)


94 FLOWR Semantics


1 10 1 true -5 (101)

2 9 4 true -4 (92)

3 8 9 true -3 (83)


(1019283746556)



3 8 9 true -3 (83)

4 7 16 true -2 (74)

5 6 25 true -1 (65)

6 5 36 true 0 (56)


94 FLOWR Semantics


let $y = $x $x

where $y lt= 42

order by 5 - $p

return ($p$x)

$x $p $y

10 1 100



return ($p$x) 10 1 100

9 2 81

8 3 64

7 4 49

6 5 36

5 6 25

4 7 16

3 8 9

2 9 4

1 10 1


3 Prune tuples

94 FLOWR Semantics

$x $p $y where

10 1 100 false

9 2 81 false



8 3 64 false

7 4 49 false

6 5 36 true

5 6 25 true

4 7 16 true

3 8 9 true

2 9 4 true

1 10 1 true

$x $p $y where

6 5 36 true

5 6 25 true

4 7 16 true

3 8 9 true

2 9 4 true

1 10 1 true



94 FLOWR Semantics

$x $p $y order by

6 5 36 0

5 6 25 -1



4 7 16 -2

3 8 9 -3

2 9 4 -4

1 10 1 -5


6 5 36 6 (56)

5 6 25 5 (65)

4 7 16 4 (74)

3 8 9 3 (83)

2 9 4 2 (92)

1 10 1 1 (101)



94 FLOWR Semantics


ltxgtltygt12ltygt

ltygt10ltygt

ltygt7ltygt

let $x =

ltxgtltygt12ltygt

ltygt10ltygt

ltygt7ltygt



ltygt7ltygt

ltygt13ltygt

ltxgt

let $sum = 0

for $y in $xy


return $sum

ltygt7ltygt

ltygt13ltygt

ltxgt

for $y in $xy

return 0 + $y

91 Introduction

92 Preliminaries


9 XQuery

94 FLWOR Semantics































ndash Definition


















ltentrygt



element


$e $enode()






rArrrArrrArrrArr



















˽)



˽)


let $n = ltxgt

ltygtltzgt

ltxgtname()








ltxgt

ltygt

xyxml





ltygt

ltxgt












count(


()[1] ltxgtnode())

ndash Solution



x

text y

z








return


attribute id 1



ndash



y y


x

notnotnotnotis







let $x = ltxgt

return $x is $x

let $d = doc(uri)





let $x = ltxgt

let $y = ltygt







Solution


ndash A join query




ltagt





ltxgt

for $c in $abc



Result





ltagt





ltxgt

for $c in $abc

return ltgroupgt



ltgroupgt








larr empty group













return ltgroupgt




return ltgroupgt

ltcgt $c ltcgt


ltgroupgt

91 Introduction

92 Preliminaries


9 XQuery

94 FLWOR Semantics























[Gru08]


return fnname($a) )


return $adpath()





Reverse a sequence





[Gru08]



return $i





[Gru08]





Questions











[Gru08]


localhmm(ltagtltbgt


ltagt)





$from as xsstring

$to as xsstring)

typeswitch ($n)


[Gru08]



return

element

node-name($e)

$e( except $a)


else ()

for $c in $enode()


default return $n






Invoke xlate


foo

lty zoo=1gtbarltygt

ltxgt

foo

dArrdArrdArrdArr





foo

bar)

dArrdArrdArrdArr

ltx id=0 bar=gt

foo

lty zoo=1gtbarltygt

ltxgt



bull (namespaces)


bull (namespaces)





1 Introduction

2 XML Basics

3 Schema definition






97 Overview

uumluumluumluuml

uumluumluumluuml

uumluuml


to XML

6 SQLXML

7 XML processing


11 XML storage II


13 Systems


uumluumluumluuml

uumluuml




97 References

ndash M Scholl








97 References





bull Now or

bull Room IZ 232




or on appointment





92 Preliminaries

Function Example












92 Preliminaries









91 Introduction

92 Preliminaries



9 XQuery


ndash Where clause

94 FLWOR Semantics











ndash groupings















Iteration examples

for $x in (321)


for $x in (321)


for $x in (321)


2a2b



return ($x$y)


1a1b)

FLWOR Abbreviations

for $v1 in e1return






return e3







A sample csa

b c

d

e g h

f


b

e

c

d

g h

f

1

3 3 3

Answer








return e[$i]

for $i at $p in e


then e[$p]

else ()













for $x in (321)

return ($x)


)



let $x = (321)

return ($x)





then $seq[$p]

else ()





A where clause




for $v in e1where p

return e2

equiv


then e2else ()




a[b = foo]c[2]d[e = 42]

for $a in a



for $a in a

where $ab = foo


where $p = 2


where $de = 42

return $d




In the FLWOR block


In the FLWOR block






for $x at $p in (53142)

order by $p

return $x




for $x at $p in (53142)

order by $p + $x

return $x



for $x at $p in (53142)

order by $x

return $x






ltb id=0gt42ltbgt

ltb id=1gt5ltbgt


ltb id=1gt5ltbgt

ltb id=2gt

ltb id=3gt3ltbgt

ltb id=4gt1ltbgt

ltagt



return $bid

Answer

91 Introduction

92 Preliminaries


9 XQuery

94 FLWOR Semantics






94 FLOWR Semantics









94 FLOWR Semantics


let $y = $x $x

where $y lt= 42

order by 5 - $p

return ($p$x)


10 1 100 false 4 (110)



return ($p$x) 10 1 100 false 4 (110)

9 2 81 false 3 (29)

8 3 64 false 2 (38)

7 4 49 false 1 (47)

6 5 36 true 0 (56)

5 6 25 true -1 (65)

4 7 16 true -2 (74)

3 8 9 true -3 (83)

2 9 4 true -4 (92)

1 10 1 true -5 (101)


94 FLOWR Semantics


10 1 100 false 4 (110)

9 2 81 false 3 (29)

8 3 64 false 2 (38)


8 3 64 false 2 (38)

7 4 49 false 1 (47)

6 5 36 true 0 (56)

5 6 25 true -1 (65)

4 7 16 true -2 (74)

3 8 9 true -3 (83)

2 9 4 true -4 (92)

1 10 1 true -5 (101)


94 FLOWR Semantics


1 10 1 true -5 (101)

2 9 4 true -4 (92)

3 8 9 true -3 (83)


(1019283746556)



3 8 9 true -3 (83)

4 7 16 true -2 (74)

5 6 25 true -1 (65)

6 5 36 true 0 (56)


94 FLOWR Semantics


let $y = $x $x

where $y lt= 42

order by 5 - $p

return ($p$x)

$x $p $y

10 1 100



return ($p$x) 10 1 100

9 2 81

8 3 64

7 4 49

6 5 36

5 6 25

4 7 16

3 8 9

2 9 4

1 10 1


3 Prune tuples

94 FLOWR Semantics

$x $p $y where

10 1 100 false

9 2 81 false



8 3 64 false

7 4 49 false

6 5 36 true

5 6 25 true

4 7 16 true

3 8 9 true

2 9 4 true

1 10 1 true

$x $p $y where

6 5 36 true

5 6 25 true

4 7 16 true

3 8 9 true

2 9 4 true

1 10 1 true



94 FLOWR Semantics

$x $p $y order by

6 5 36 0

5 6 25 -1



4 7 16 -2

3 8 9 -3

2 9 4 -4

1 10 1 -5


6 5 36 6 (56)

5 6 25 5 (65)

4 7 16 4 (74)

3 8 9 3 (83)

2 9 4 2 (92)

1 10 1 1 (101)



94 FLOWR Semantics


ltxgtltygt12ltygt

ltygt10ltygt

ltygt7ltygt

let $x =

ltxgtltygt12ltygt

ltygt10ltygt

ltygt7ltygt



ltygt7ltygt

ltygt13ltygt

ltxgt

let $sum = 0

for $y in $xy


return $sum

ltygt7ltygt

ltygt13ltygt

ltxgt

for $y in $xy

return 0 + $y

91 Introduction

92 Preliminaries


9 XQuery

94 FLWOR Semantics































ndash Definition


















ltentrygt



element


$e $enode()






rArrrArrrArrrArr



















˽)



˽)


let $n = ltxgt

ltygtltzgt

ltxgtname()








ltxgt

ltygt

xyxml





ltygt

ltxgt












count(


()[1] ltxgtnode())

ndash Solution



x

text y

z








return


attribute id 1



ndash



y y


x

notnotnotnotis







let $x = ltxgt

return $x is $x

let $d = doc(uri)





let $x = ltxgt

let $y = ltygt







Solution


ndash A join query




ltagt





ltxgt

for $c in $abc



Result





ltagt





ltxgt

for $c in $abc

return ltgroupgt



ltgroupgt








larr empty group













return ltgroupgt




return ltgroupgt

ltcgt $c ltcgt


ltgroupgt

91 Introduction

92 Preliminaries


9 XQuery

94 FLWOR Semantics























[Gru08]


return fnname($a) )


return $adpath()





Reverse a sequence





[Gru08]



return $i





[Gru08]





Questions











[Gru08]


localhmm(ltagtltbgt


ltagt)





$from as xsstring

$to as xsstring)

typeswitch ($n)


[Gru08]



return

element

node-name($e)

$e( except $a)


else ()

for $c in $enode()


default return $n






Invoke xlate


foo

lty zoo=1gtbarltygt

ltxgt

foo

dArrdArrdArrdArr





foo

bar)

dArrdArrdArrdArr

ltx id=0 bar=gt

foo

lty zoo=1gtbarltygt

ltxgt



bull (namespaces)


bull (namespaces)





1 Introduction

2 XML Basics

3 Schema definition






97 Overview

uumluumluumluuml

uumluumluumluuml

uumluuml


to XML

6 SQLXML

7 XML processing


11 XML storage II


13 Systems


uumluumluumluuml

uumluuml




97 References

ndash M Scholl








97 References





bull Now or

bull Room IZ 232




or on appointment





92 Preliminaries









91 Introduction

92 Preliminaries



9 XQuery


ndash Where clause

94 FLWOR Semantics











ndash groupings















Iteration examples

for $x in (321)


for $x in (321)


for $x in (321)


2a2b



return ($x$y)


1a1b)

FLWOR Abbreviations

for $v1 in e1return






return e3







A sample csa

b c

d

e g h

f


b

e

c

d

g h

f

1

3 3 3

Answer








return e[$i]

for $i at $p in e


then e[$p]

else ()













for $x in (321)

return ($x)


)



let $x = (321)

return ($x)





then $seq[$p]

else ()





A where clause




for $v in e1where p

return e2

equiv


then e2else ()




a[b = foo]c[2]d[e = 42]

for $a in a



for $a in a

where $ab = foo


where $p = 2


where $de = 42

return $d




In the FLWOR block


In the FLWOR block






for $x at $p in (53142)

order by $p

return $x




for $x at $p in (53142)

order by $p + $x

return $x



for $x at $p in (53142)

order by $x

return $x






ltb id=0gt42ltbgt

ltb id=1gt5ltbgt


ltb id=1gt5ltbgt

ltb id=2gt

ltb id=3gt3ltbgt

ltb id=4gt1ltbgt

ltagt



return $bid

Answer

91 Introduction

92 Preliminaries


9 XQuery

94 FLWOR Semantics






94 FLOWR Semantics









94 FLOWR Semantics


let $y = $x $x

where $y lt= 42

order by 5 - $p

return ($p$x)


10 1 100 false 4 (110)



return ($p$x) 10 1 100 false 4 (110)

9 2 81 false 3 (29)

8 3 64 false 2 (38)

7 4 49 false 1 (47)

6 5 36 true 0 (56)

5 6 25 true -1 (65)

4 7 16 true -2 (74)

3 8 9 true -3 (83)

2 9 4 true -4 (92)

1 10 1 true -5 (101)


94 FLOWR Semantics


10 1 100 false 4 (110)

9 2 81 false 3 (29)

8 3 64 false 2 (38)


8 3 64 false 2 (38)

7 4 49 false 1 (47)

6 5 36 true 0 (56)

5 6 25 true -1 (65)

4 7 16 true -2 (74)

3 8 9 true -3 (83)

2 9 4 true -4 (92)

1 10 1 true -5 (101)


94 FLOWR Semantics


1 10 1 true -5 (101)

2 9 4 true -4 (92)

3 8 9 true -3 (83)


(1019283746556)



3 8 9 true -3 (83)

4 7 16 true -2 (74)

5 6 25 true -1 (65)

6 5 36 true 0 (56)


94 FLOWR Semantics


let $y = $x $x

where $y lt= 42

order by 5 - $p

return ($p$x)

$x $p $y

10 1 100



return ($p$x) 10 1 100

9 2 81

8 3 64

7 4 49

6 5 36

5 6 25

4 7 16

3 8 9

2 9 4

1 10 1


3 Prune tuples

94 FLOWR Semantics

$x $p $y where

10 1 100 false

9 2 81 false



8 3 64 false

7 4 49 false

6 5 36 true

5 6 25 true

4 7 16 true

3 8 9 true

2 9 4 true

1 10 1 true

$x $p $y where

6 5 36 true

5 6 25 true

4 7 16 true

3 8 9 true

2 9 4 true

1 10 1 true



94 FLOWR Semantics

$x $p $y order by

6 5 36 0

5 6 25 -1



4 7 16 -2

3 8 9 -3

2 9 4 -4

1 10 1 -5


6 5 36 6 (56)

5 6 25 5 (65)

4 7 16 4 (74)

3 8 9 3 (83)

2 9 4 2 (92)

1 10 1 1 (101)



94 FLOWR Semantics


ltxgtltygt12ltygt

ltygt10ltygt

ltygt7ltygt

let $x =

ltxgtltygt12ltygt

ltygt10ltygt

ltygt7ltygt



ltygt7ltygt

ltygt13ltygt

ltxgt

let $sum = 0

for $y in $xy


return $sum

ltygt7ltygt

ltygt13ltygt

ltxgt

for $y in $xy

return 0 + $y

91 Introduction

92 Preliminaries


9 XQuery

94 FLWOR Semantics































ndash Definition


















ltentrygt



element


$e $enode()






rArrrArrrArrrArr



















˽)



˽)


let $n = ltxgt

ltygtltzgt

ltxgtname()








ltxgt

ltygt

xyxml





ltygt

ltxgt












count(


()[1] ltxgtnode())

ndash Solution



x

text y

z








return


attribute id 1



ndash



y y


x

notnotnotnotis







let $x = ltxgt

return $x is $x

let $d = doc(uri)





let $x = ltxgt

let $y = ltygt







Solution


ndash A join query




ltagt





ltxgt

for $c in $abc



Result





ltagt





ltxgt

for $c in $abc

return ltgroupgt



ltgroupgt








larr empty group













return ltgroupgt




return ltgroupgt

ltcgt $c ltcgt


ltgroupgt

91 Introduction

92 Preliminaries


9 XQuery

94 FLWOR Semantics























[Gru08]


return fnname($a) )


return $adpath()





Reverse a sequence





[Gru08]



return $i





[Gru08]





Questions











[Gru08]


localhmm(ltagtltbgt


ltagt)





$from as xsstring

$to as xsstring)

typeswitch ($n)


[Gru08]



return

element

node-name($e)

$e( except $a)


else ()

for $c in $enode()


default return $n






Invoke xlate


foo

lty zoo=1gtbarltygt

ltxgt

foo

dArrdArrdArrdArr





foo

bar)

dArrdArrdArrdArr

ltx id=0 bar=gt

foo

lty zoo=1gtbarltygt

ltxgt



bull (namespaces)


bull (namespaces)





1 Introduction

2 XML Basics

3 Schema definition






97 Overview

uumluumluumluuml

uumluumluumluuml

uumluuml


to XML

6 SQLXML

7 XML processing


11 XML storage II


13 Systems


uumluumluumluuml

uumluuml




97 References

ndash M Scholl








97 References





bull Now or

bull Room IZ 232




or on appointment



91 Introduction

92 Preliminaries



9 XQuery


ndash Where clause

94 FLWOR Semantics











ndash groupings















Iteration examples

for $x in (321)


for $x in (321)


for $x in (321)


2a2b



return ($x$y)


1a1b)

FLWOR Abbreviations

for $v1 in e1return






return e3







A sample csa

b c

d

e g h

f


b

e

c

d

g h

f

1

3 3 3

Answer








return e[$i]

for $i at $p in e


then e[$p]

else ()













for $x in (321)

return ($x)


)



let $x = (321)

return ($x)





then $seq[$p]

else ()





A where clause




for $v in e1where p

return e2

equiv


then e2else ()




a[b = foo]c[2]d[e = 42]

for $a in a



for $a in a

where $ab = foo


where $p = 2


where $de = 42

return $d




In the FLWOR block


In the FLWOR block






for $x at $p in (53142)

order by $p

return $x




for $x at $p in (53142)

order by $p + $x

return $x



for $x at $p in (53142)

order by $x

return $x






ltb id=0gt42ltbgt

ltb id=1gt5ltbgt


ltb id=1gt5ltbgt

ltb id=2gt

ltb id=3gt3ltbgt

ltb id=4gt1ltbgt

ltagt



return $bid

Answer

91 Introduction

92 Preliminaries


9 XQuery

94 FLWOR Semantics






94 FLOWR Semantics









94 FLOWR Semantics


let $y = $x $x

where $y lt= 42

order by 5 - $p

return ($p$x)


10 1 100 false 4 (110)



return ($p$x) 10 1 100 false 4 (110)

9 2 81 false 3 (29)

8 3 64 false 2 (38)

7 4 49 false 1 (47)

6 5 36 true 0 (56)

5 6 25 true -1 (65)

4 7 16 true -2 (74)

3 8 9 true -3 (83)

2 9 4 true -4 (92)

1 10 1 true -5 (101)


94 FLOWR Semantics


10 1 100 false 4 (110)

9 2 81 false 3 (29)

8 3 64 false 2 (38)


8 3 64 false 2 (38)

7 4 49 false 1 (47)

6 5 36 true 0 (56)

5 6 25 true -1 (65)

4 7 16 true -2 (74)

3 8 9 true -3 (83)

2 9 4 true -4 (92)

1 10 1 true -5 (101)


94 FLOWR Semantics


1 10 1 true -5 (101)

2 9 4 true -4 (92)

3 8 9 true -3 (83)


(1019283746556)



3 8 9 true -3 (83)

4 7 16 true -2 (74)

5 6 25 true -1 (65)

6 5 36 true 0 (56)


94 FLOWR Semantics


let $y = $x $x

where $y lt= 42

order by 5 - $p

return ($p$x)

$x $p $y

10 1 100



return ($p$x) 10 1 100

9 2 81

8 3 64

7 4 49

6 5 36

5 6 25

4 7 16

3 8 9

2 9 4

1 10 1


3 Prune tuples

94 FLOWR Semantics

$x $p $y where

10 1 100 false

9 2 81 false



8 3 64 false

7 4 49 false

6 5 36 true

5 6 25 true

4 7 16 true

3 8 9 true

2 9 4 true

1 10 1 true

$x $p $y where

6 5 36 true

5 6 25 true

4 7 16 true

3 8 9 true

2 9 4 true

1 10 1 true



94 FLOWR Semantics

$x $p $y order by

6 5 36 0

5 6 25 -1



4 7 16 -2

3 8 9 -3

2 9 4 -4

1 10 1 -5


6 5 36 6 (56)

5 6 25 5 (65)

4 7 16 4 (74)

3 8 9 3 (83)

2 9 4 2 (92)

1 10 1 1 (101)



94 FLOWR Semantics


ltxgtltygt12ltygt

ltygt10ltygt

ltygt7ltygt

let $x =

ltxgtltygt12ltygt

ltygt10ltygt

ltygt7ltygt



ltygt7ltygt

ltygt13ltygt

ltxgt

let $sum = 0

for $y in $xy


return $sum

ltygt7ltygt

ltygt13ltygt

ltxgt

for $y in $xy

return 0 + $y

91 Introduction

92 Preliminaries


9 XQuery

94 FLWOR Semantics































ndash Definition


















ltentrygt



element


$e $enode()






rArrrArrrArrrArr



















˽)



˽)


let $n = ltxgt

ltygtltzgt

ltxgtname()








ltxgt

ltygt

xyxml





ltygt

ltxgt












count(


()[1] ltxgtnode())

ndash Solution



x

text y

z








return


attribute id 1



ndash



y y


x

notnotnotnotis







let $x = ltxgt

return $x is $x

let $d = doc(uri)





let $x = ltxgt

let $y = ltygt







Solution


ndash A join query




ltagt





ltxgt

for $c in $abc



Result





ltagt





ltxgt

for $c in $abc

return ltgroupgt



ltgroupgt








larr empty group













return ltgroupgt




return ltgroupgt

ltcgt $c ltcgt


ltgroupgt

91 Introduction

92 Preliminaries


9 XQuery

94 FLWOR Semantics























[Gru08]


return fnname($a) )


return $adpath()





Reverse a sequence





[Gru08]



return $i





[Gru08]





Questions











[Gru08]


localhmm(ltagtltbgt


ltagt)





$from as xsstring

$to as xsstring)

typeswitch ($n)


[Gru08]



return

element

node-name($e)

$e( except $a)


else ()

for $c in $enode()


default return $n






Invoke xlate


foo

lty zoo=1gtbarltygt

ltxgt

foo

dArrdArrdArrdArr





foo

bar)

dArrdArrdArrdArr

ltx id=0 bar=gt

foo

lty zoo=1gtbarltygt

ltxgt



bull (namespaces)


bull (namespaces)





1 Introduction

2 XML Basics

3 Schema definition






97 Overview

uumluumluumluuml

uumluumluumluuml

uumluuml


to XML

6 SQLXML

7 XML processing


11 XML storage II


13 Systems


uumluumluumluuml

uumluuml




97 References

ndash M Scholl








97 References





bull Now or

bull Room IZ 232




or on appointment









ndash groupings















Iteration examples

for $x in (321)


for $x in (321)


for $x in (321)


2a2b



return ($x$y)


1a1b)

FLWOR Abbreviations

for $v1 in e1return






return e3







A sample csa

b c

d

e g h

f


b

e

c

d

g h

f

1

3 3 3

Answer








return e[$i]

for $i at $p in e


then e[$p]

else ()













for $x in (321)

return ($x)


)



let $x = (321)

return ($x)





then $seq[$p]

else ()





A where clause




for $v in e1where p

return e2

equiv


then e2else ()




a[b = foo]c[2]d[e = 42]

for $a in a



for $a in a

where $ab = foo


where $p = 2


where $de = 42

return $d




In the FLWOR block


In the FLWOR block






for $x at $p in (53142)

order by $p

return $x




for $x at $p in (53142)

order by $p + $x

return $x



for $x at $p in (53142)

order by $x

return $x






ltb id=0gt42ltbgt

ltb id=1gt5ltbgt


ltb id=1gt5ltbgt

ltb id=2gt

ltb id=3gt3ltbgt

ltb id=4gt1ltbgt

ltagt



return $bid

Answer

91 Introduction

92 Preliminaries


9 XQuery

94 FLWOR Semantics






94 FLOWR Semantics









94 FLOWR Semantics


let $y = $x $x

where $y lt= 42

order by 5 - $p

return ($p$x)


10 1 100 false 4 (110)



return ($p$x) 10 1 100 false 4 (110)

9 2 81 false 3 (29)

8 3 64 false 2 (38)

7 4 49 false 1 (47)

6 5 36 true 0 (56)

5 6 25 true -1 (65)

4 7 16 true -2 (74)

3 8 9 true -3 (83)

2 9 4 true -4 (92)

1 10 1 true -5 (101)


94 FLOWR Semantics


10 1 100 false 4 (110)

9 2 81 false 3 (29)

8 3 64 false 2 (38)


8 3 64 false 2 (38)

7 4 49 false 1 (47)

6 5 36 true 0 (56)

5 6 25 true -1 (65)

4 7 16 true -2 (74)

3 8 9 true -3 (83)

2 9 4 true -4 (92)

1 10 1 true -5 (101)


94 FLOWR Semantics


1 10 1 true -5 (101)

2 9 4 true -4 (92)

3 8 9 true -3 (83)


(1019283746556)



3 8 9 true -3 (83)

4 7 16 true -2 (74)

5 6 25 true -1 (65)

6 5 36 true 0 (56)


94 FLOWR Semantics


let $y = $x $x

where $y lt= 42

order by 5 - $p

return ($p$x)

$x $p $y

10 1 100



return ($p$x) 10 1 100

9 2 81

8 3 64

7 4 49

6 5 36

5 6 25

4 7 16

3 8 9

2 9 4

1 10 1


3 Prune tuples

94 FLOWR Semantics

$x $p $y where

10 1 100 false

9 2 81 false



8 3 64 false

7 4 49 false

6 5 36 true

5 6 25 true

4 7 16 true

3 8 9 true

2 9 4 true

1 10 1 true

$x $p $y where

6 5 36 true

5 6 25 true

4 7 16 true

3 8 9 true

2 9 4 true

1 10 1 true



94 FLOWR Semantics

$x $p $y order by

6 5 36 0

5 6 25 -1



4 7 16 -2

3 8 9 -3

2 9 4 -4

1 10 1 -5


6 5 36 6 (56)

5 6 25 5 (65)

4 7 16 4 (74)

3 8 9 3 (83)

2 9 4 2 (92)

1 10 1 1 (101)



94 FLOWR Semantics


ltxgtltygt12ltygt

ltygt10ltygt

ltygt7ltygt

let $x =

ltxgtltygt12ltygt

ltygt10ltygt

ltygt7ltygt



ltygt7ltygt

ltygt13ltygt

ltxgt

let $sum = 0

for $y in $xy


return $sum

ltygt7ltygt

ltygt13ltygt

ltxgt

for $y in $xy

return 0 + $y

91 Introduction

92 Preliminaries


9 XQuery

94 FLWOR Semantics































ndash Definition


















ltentrygt



element


$e $enode()






rArrrArrrArrrArr



















˽)



˽)


let $n = ltxgt

ltygtltzgt

ltxgtname()








ltxgt

ltygt

xyxml





ltygt

ltxgt












count(


()[1] ltxgtnode())

ndash Solution



x

text y

z








return


attribute id 1



ndash



y y


x

notnotnotnotis







let $x = ltxgt

return $x is $x

let $d = doc(uri)





let $x = ltxgt

let $y = ltygt







Solution


ndash A join query




ltagt





ltxgt

for $c in $abc



Result





ltagt





ltxgt

for $c in $abc

return ltgroupgt



ltgroupgt








larr empty group













return ltgroupgt




return ltgroupgt

ltcgt $c ltcgt


ltgroupgt

91 Introduction

92 Preliminaries


9 XQuery

94 FLWOR Semantics























[Gru08]


return fnname($a) )


return $adpath()





Reverse a sequence





[Gru08]



return $i





[Gru08]





Questions











[Gru08]


localhmm(ltagtltbgt


ltagt)





$from as xsstring

$to as xsstring)

typeswitch ($n)


[Gru08]



return

element

node-name($e)

$e( except $a)


else ()

for $c in $enode()


default return $n






Invoke xlate


foo

lty zoo=1gtbarltygt

ltxgt

foo

dArrdArrdArrdArr





foo

bar)

dArrdArrdArrdArr

ltx id=0 bar=gt

foo

lty zoo=1gtbarltygt

ltxgt



bull (namespaces)


bull (namespaces)





1 Introduction

2 XML Basics

3 Schema definition






97 Overview

uumluumluumluuml

uumluumluumluuml

uumluuml


to XML

6 SQLXML

7 XML processing


11 XML storage II


13 Systems


uumluumluumluuml

uumluuml




97 References

ndash M Scholl








97 References





bull Now or

bull Room IZ 232




or on appointment














Iteration examples

for $x in (321)


for $x in (321)


for $x in (321)


2a2b



return ($x$y)


1a1b)

FLWOR Abbreviations

for $v1 in e1return






return e3







A sample csa

b c

d

e g h

f


b

e

c

d

g h

f

1

3 3 3

Answer








return e[$i]

for $i at $p in e


then e[$p]

else ()













for $x in (321)

return ($x)


)



let $x = (321)

return ($x)





then $seq[$p]

else ()





A where clause




for $v in e1where p

return e2

equiv


then e2else ()




a[b = foo]c[2]d[e = 42]

for $a in a



for $a in a

where $ab = foo


where $p = 2


where $de = 42

return $d




In the FLWOR block


In the FLWOR block






for $x at $p in (53142)

order by $p

return $x




for $x at $p in (53142)

order by $p + $x

return $x



for $x at $p in (53142)

order by $x

return $x






ltb id=0gt42ltbgt

ltb id=1gt5ltbgt


ltb id=1gt5ltbgt

ltb id=2gt

ltb id=3gt3ltbgt

ltb id=4gt1ltbgt

ltagt



return $bid

Answer

91 Introduction

92 Preliminaries


9 XQuery

94 FLWOR Semantics






94 FLOWR Semantics









94 FLOWR Semantics


let $y = $x $x

where $y lt= 42

order by 5 - $p

return ($p$x)


10 1 100 false 4 (110)



return ($p$x) 10 1 100 false 4 (110)

9 2 81 false 3 (29)

8 3 64 false 2 (38)

7 4 49 false 1 (47)

6 5 36 true 0 (56)

5 6 25 true -1 (65)

4 7 16 true -2 (74)

3 8 9 true -3 (83)

2 9 4 true -4 (92)

1 10 1 true -5 (101)


94 FLOWR Semantics


10 1 100 false 4 (110)

9 2 81 false 3 (29)

8 3 64 false 2 (38)


8 3 64 false 2 (38)

7 4 49 false 1 (47)

6 5 36 true 0 (56)

5 6 25 true -1 (65)

4 7 16 true -2 (74)

3 8 9 true -3 (83)

2 9 4 true -4 (92)

1 10 1 true -5 (101)


94 FLOWR Semantics


1 10 1 true -5 (101)

2 9 4 true -4 (92)

3 8 9 true -3 (83)


(1019283746556)



3 8 9 true -3 (83)

4 7 16 true -2 (74)

5 6 25 true -1 (65)

6 5 36 true 0 (56)


94 FLOWR Semantics


let $y = $x $x

where $y lt= 42

order by 5 - $p

return ($p$x)

$x $p $y

10 1 100



return ($p$x) 10 1 100

9 2 81

8 3 64

7 4 49

6 5 36

5 6 25

4 7 16

3 8 9

2 9 4

1 10 1


3 Prune tuples

94 FLOWR Semantics

$x $p $y where

10 1 100 false

9 2 81 false



8 3 64 false

7 4 49 false

6 5 36 true

5 6 25 true

4 7 16 true

3 8 9 true

2 9 4 true

1 10 1 true

$x $p $y where

6 5 36 true

5 6 25 true

4 7 16 true

3 8 9 true

2 9 4 true

1 10 1 true



94 FLOWR Semantics

$x $p $y order by

6 5 36 0

5 6 25 -1



4 7 16 -2

3 8 9 -3

2 9 4 -4

1 10 1 -5


6 5 36 6 (56)

5 6 25 5 (65)

4 7 16 4 (74)

3 8 9 3 (83)

2 9 4 2 (92)

1 10 1 1 (101)



94 FLOWR Semantics


ltxgtltygt12ltygt

ltygt10ltygt

ltygt7ltygt

let $x =

ltxgtltygt12ltygt

ltygt10ltygt

ltygt7ltygt



ltygt7ltygt

ltygt13ltygt

ltxgt

let $sum = 0

for $y in $xy


return $sum

ltygt7ltygt

ltygt13ltygt

ltxgt

for $y in $xy

return 0 + $y

91 Introduction

92 Preliminaries


9 XQuery

94 FLWOR Semantics































ndash Definition


















ltentrygt



element


$e $enode()






rArrrArrrArrrArr



















˽)



˽)


let $n = ltxgt

ltygtltzgt

ltxgtname()








ltxgt

ltygt

xyxml





ltygt

ltxgt












count(


()[1] ltxgtnode())

ndash Solution



x

text y

z








return


attribute id 1



ndash



y y


x

notnotnotnotis







let $x = ltxgt

return $x is $x

let $d = doc(uri)





let $x = ltxgt

let $y = ltygt







Solution


ndash A join query




ltagt





ltxgt

for $c in $abc



Result





ltagt





ltxgt

for $c in $abc

return ltgroupgt



ltgroupgt








larr empty group













return ltgroupgt




return ltgroupgt

ltcgt $c ltcgt


ltgroupgt

91 Introduction

92 Preliminaries


9 XQuery

94 FLWOR Semantics























[Gru08]


return fnname($a) )


return $adpath()





Reverse a sequence





[Gru08]



return $i





[Gru08]





Questions











[Gru08]


localhmm(ltagtltbgt


ltagt)





$from as xsstring

$to as xsstring)

typeswitch ($n)


[Gru08]



return

element

node-name($e)

$e( except $a)


else ()

for $c in $enode()


default return $n






Invoke xlate


foo

lty zoo=1gtbarltygt

ltxgt

foo

dArrdArrdArrdArr





foo

bar)

dArrdArrdArrdArr

ltx id=0 bar=gt

foo

lty zoo=1gtbarltygt

ltxgt



bull (namespaces)


bull (namespaces)





1 Introduction

2 XML Basics

3 Schema definition






97 Overview

uumluumluumluuml

uumluumluumluuml

uumluuml


to XML

6 SQLXML

7 XML processing


11 XML storage II


13 Systems


uumluumluumluuml

uumluuml




97 References

ndash M Scholl








97 References





bull Now or

bull Room IZ 232




or on appointment









A sample csa

b c

d

e g h

f


b

e

c

d

g h

f

1

3 3 3

Answer








return e[$i]

for $i at $p in e


then e[$p]

else ()













for $x in (321)

return ($x)


)



let $x = (321)

return ($x)





then $seq[$p]

else ()





A where clause




for $v in e1where p

return e2

equiv


then e2else ()




a[b = foo]c[2]d[e = 42]

for $a in a



for $a in a

where $ab = foo


where $p = 2


where $de = 42

return $d




In the FLWOR block


In the FLWOR block






for $x at $p in (53142)

order by $p

return $x




for $x at $p in (53142)

order by $p + $x

return $x



for $x at $p in (53142)

order by $x

return $x






ltb id=0gt42ltbgt

ltb id=1gt5ltbgt


ltb id=1gt5ltbgt

ltb id=2gt

ltb id=3gt3ltbgt

ltb id=4gt1ltbgt

ltagt



return $bid

Answer

91 Introduction

92 Preliminaries


9 XQuery

94 FLWOR Semantics






94 FLOWR Semantics









94 FLOWR Semantics


let $y = $x $x

where $y lt= 42

order by 5 - $p

return ($p$x)


10 1 100 false 4 (110)



return ($p$x) 10 1 100 false 4 (110)

9 2 81 false 3 (29)

8 3 64 false 2 (38)

7 4 49 false 1 (47)

6 5 36 true 0 (56)

5 6 25 true -1 (65)

4 7 16 true -2 (74)

3 8 9 true -3 (83)

2 9 4 true -4 (92)

1 10 1 true -5 (101)


94 FLOWR Semantics


10 1 100 false 4 (110)

9 2 81 false 3 (29)

8 3 64 false 2 (38)


8 3 64 false 2 (38)

7 4 49 false 1 (47)

6 5 36 true 0 (56)

5 6 25 true -1 (65)

4 7 16 true -2 (74)

3 8 9 true -3 (83)

2 9 4 true -4 (92)

1 10 1 true -5 (101)


94 FLOWR Semantics


1 10 1 true -5 (101)

2 9 4 true -4 (92)

3 8 9 true -3 (83)


(1019283746556)



3 8 9 true -3 (83)

4 7 16 true -2 (74)

5 6 25 true -1 (65)

6 5 36 true 0 (56)


94 FLOWR Semantics


let $y = $x $x

where $y lt= 42

order by 5 - $p

return ($p$x)

$x $p $y

10 1 100



return ($p$x) 10 1 100

9 2 81

8 3 64

7 4 49

6 5 36

5 6 25

4 7 16

3 8 9

2 9 4

1 10 1


3 Prune tuples

94 FLOWR Semantics

$x $p $y where

10 1 100 false

9 2 81 false



8 3 64 false

7 4 49 false

6 5 36 true

5 6 25 true

4 7 16 true

3 8 9 true

2 9 4 true

1 10 1 true

$x $p $y where

6 5 36 true

5 6 25 true

4 7 16 true

3 8 9 true

2 9 4 true

1 10 1 true



94 FLOWR Semantics

$x $p $y order by

6 5 36 0

5 6 25 -1



4 7 16 -2

3 8 9 -3

2 9 4 -4

1 10 1 -5


6 5 36 6 (56)

5 6 25 5 (65)

4 7 16 4 (74)

3 8 9 3 (83)

2 9 4 2 (92)

1 10 1 1 (101)



94 FLOWR Semantics


ltxgtltygt12ltygt

ltygt10ltygt

ltygt7ltygt

let $x =

ltxgtltygt12ltygt

ltygt10ltygt

ltygt7ltygt



ltygt7ltygt

ltygt13ltygt

ltxgt

let $sum = 0

for $y in $xy


return $sum

ltygt7ltygt

ltygt13ltygt

ltxgt

for $y in $xy

return 0 + $y

91 Introduction

92 Preliminaries


9 XQuery

94 FLWOR Semantics































ndash Definition


















ltentrygt



element


$e $enode()






rArrrArrrArrrArr



















˽)



˽)


let $n = ltxgt

ltygtltzgt

ltxgtname()








ltxgt

ltygt

xyxml





ltygt

ltxgt












count(


()[1] ltxgtnode())

ndash Solution



x

text y

z








return


attribute id 1



ndash



y y


x

notnotnotnotis







let $x = ltxgt

return $x is $x

let $d = doc(uri)





let $x = ltxgt

let $y = ltygt







Solution


ndash A join query




ltagt





ltxgt

for $c in $abc



Result





ltagt





ltxgt

for $c in $abc

return ltgroupgt



ltgroupgt








larr empty group













return ltgroupgt




return ltgroupgt

ltcgt $c ltcgt


ltgroupgt

91 Introduction

92 Preliminaries


9 XQuery

94 FLWOR Semantics























[Gru08]


return fnname($a) )


return $adpath()





Reverse a sequence





[Gru08]



return $i





[Gru08]





Questions











[Gru08]


localhmm(ltagtltbgt


ltagt)





$from as xsstring

$to as xsstring)

typeswitch ($n)


[Gru08]



return

element

node-name($e)

$e( except $a)


else ()

for $c in $enode()


default return $n






Invoke xlate


foo

lty zoo=1gtbarltygt

ltxgt

foo

dArrdArrdArrdArr





foo

bar)

dArrdArrdArrdArr

ltx id=0 bar=gt

foo

lty zoo=1gtbarltygt

ltxgt



bull (namespaces)


bull (namespaces)





1 Introduction

2 XML Basics

3 Schema definition






97 Overview

uumluumluumluuml

uumluumluumluuml

uumluuml


to XML

6 SQLXML

7 XML processing


11 XML storage II


13 Systems


uumluumluumluuml

uumluuml




97 References

ndash M Scholl








97 References





bull Now or

bull Room IZ 232




or on appointment










return e[$i]

for $i at $p in e


then e[$p]

else ()













for $x in (321)

return ($x)


)



let $x = (321)

return ($x)





then $seq[$p]

else ()





A where clause




for $v in e1where p

return e2

equiv


then e2else ()




a[b = foo]c[2]d[e = 42]

for $a in a



for $a in a

where $ab = foo


where $p = 2


where $de = 42

return $d




In the FLWOR block


In the FLWOR block






for $x at $p in (53142)

order by $p

return $x




for $x at $p in (53142)

order by $p + $x

return $x



for $x at $p in (53142)

order by $x

return $x






ltb id=0gt42ltbgt

ltb id=1gt5ltbgt


ltb id=1gt5ltbgt

ltb id=2gt

ltb id=3gt3ltbgt

ltb id=4gt1ltbgt

ltagt



return $bid

Answer

91 Introduction

92 Preliminaries


9 XQuery

94 FLWOR Semantics






94 FLOWR Semantics









94 FLOWR Semantics


let $y = $x $x

where $y lt= 42

order by 5 - $p

return ($p$x)


10 1 100 false 4 (110)



return ($p$x) 10 1 100 false 4 (110)

9 2 81 false 3 (29)

8 3 64 false 2 (38)

7 4 49 false 1 (47)

6 5 36 true 0 (56)

5 6 25 true -1 (65)

4 7 16 true -2 (74)

3 8 9 true -3 (83)

2 9 4 true -4 (92)

1 10 1 true -5 (101)


94 FLOWR Semantics


10 1 100 false 4 (110)

9 2 81 false 3 (29)

8 3 64 false 2 (38)


8 3 64 false 2 (38)

7 4 49 false 1 (47)

6 5 36 true 0 (56)

5 6 25 true -1 (65)

4 7 16 true -2 (74)

3 8 9 true -3 (83)

2 9 4 true -4 (92)

1 10 1 true -5 (101)


94 FLOWR Semantics


1 10 1 true -5 (101)

2 9 4 true -4 (92)

3 8 9 true -3 (83)


(1019283746556)



3 8 9 true -3 (83)

4 7 16 true -2 (74)

5 6 25 true -1 (65)

6 5 36 true 0 (56)


94 FLOWR Semantics


let $y = $x $x

where $y lt= 42

order by 5 - $p

return ($p$x)

$x $p $y

10 1 100



return ($p$x) 10 1 100

9 2 81

8 3 64

7 4 49

6 5 36

5 6 25

4 7 16

3 8 9

2 9 4

1 10 1


3 Prune tuples

94 FLOWR Semantics

$x $p $y where

10 1 100 false

9 2 81 false



8 3 64 false

7 4 49 false

6 5 36 true

5 6 25 true

4 7 16 true

3 8 9 true

2 9 4 true

1 10 1 true

$x $p $y where

6 5 36 true

5 6 25 true

4 7 16 true

3 8 9 true

2 9 4 true

1 10 1 true



94 FLOWR Semantics

$x $p $y order by

6 5 36 0

5 6 25 -1



4 7 16 -2

3 8 9 -3

2 9 4 -4

1 10 1 -5


6 5 36 6 (56)

5 6 25 5 (65)

4 7 16 4 (74)

3 8 9 3 (83)

2 9 4 2 (92)

1 10 1 1 (101)



94 FLOWR Semantics


ltxgtltygt12ltygt

ltygt10ltygt

ltygt7ltygt

let $x =

ltxgtltygt12ltygt

ltygt10ltygt

ltygt7ltygt



ltygt7ltygt

ltygt13ltygt

ltxgt

let $sum = 0

for $y in $xy


return $sum

ltygt7ltygt

ltygt13ltygt

ltxgt

for $y in $xy

return 0 + $y

91 Introduction

92 Preliminaries


9 XQuery

94 FLWOR Semantics































ndash Definition


















ltentrygt



element


$e $enode()






rArrrArrrArrrArr



















˽)



˽)


let $n = ltxgt

ltygtltzgt

ltxgtname()








ltxgt

ltygt

xyxml





ltygt

ltxgt












count(


()[1] ltxgtnode())

ndash Solution



x

text y

z








return


attribute id 1



ndash



y y


x

notnotnotnotis







let $x = ltxgt

return $x is $x

let $d = doc(uri)





let $x = ltxgt

let $y = ltygt







Solution


ndash A join query




ltagt





ltxgt

for $c in $abc



Result





ltagt





ltxgt

for $c in $abc

return ltgroupgt



ltgroupgt








larr empty group













return ltgroupgt




return ltgroupgt

ltcgt $c ltcgt


ltgroupgt

91 Introduction

92 Preliminaries


9 XQuery

94 FLWOR Semantics























[Gru08]


return fnname($a) )


return $adpath()





Reverse a sequence





[Gru08]



return $i





[Gru08]





Questions











[Gru08]


localhmm(ltagtltbgt


ltagt)





$from as xsstring

$to as xsstring)

typeswitch ($n)


[Gru08]



return

element

node-name($e)

$e( except $a)


else ()

for $c in $enode()


default return $n






Invoke xlate


foo

lty zoo=1gtbarltygt

ltxgt

foo

dArrdArrdArrdArr





foo

bar)

dArrdArrdArrdArr

ltx id=0 bar=gt

foo

lty zoo=1gtbarltygt

ltxgt



bull (namespaces)


bull (namespaces)





1 Introduction

2 XML Basics

3 Schema definition






97 Overview

uumluumluumluuml

uumluumluumluuml

uumluuml


to XML

6 SQLXML

7 XML processing


11 XML storage II


13 Systems


uumluumluumluuml

uumluuml




97 References

ndash M Scholl








97 References





bull Now or

bull Room IZ 232




or on appointment















for $x in (321)

return ($x)


)



let $x = (321)

return ($x)





then $seq[$p]

else ()





A where clause




for $v in e1where p

return e2

equiv


then e2else ()




a[b = foo]c[2]d[e = 42]

for $a in a



for $a in a

where $ab = foo


where $p = 2


where $de = 42

return $d




In the FLWOR block


In the FLWOR block






for $x at $p in (53142)

order by $p

return $x




for $x at $p in (53142)

order by $p + $x

return $x



for $x at $p in (53142)

order by $x

return $x






ltb id=0gt42ltbgt

ltb id=1gt5ltbgt


ltb id=1gt5ltbgt

ltb id=2gt

ltb id=3gt3ltbgt

ltb id=4gt1ltbgt

ltagt



return $bid

Answer

91 Introduction

92 Preliminaries


9 XQuery

94 FLWOR Semantics






94 FLOWR Semantics









94 FLOWR Semantics


let $y = $x $x

where $y lt= 42

order by 5 - $p

return ($p$x)


10 1 100 false 4 (110)



return ($p$x) 10 1 100 false 4 (110)

9 2 81 false 3 (29)

8 3 64 false 2 (38)

7 4 49 false 1 (47)

6 5 36 true 0 (56)

5 6 25 true -1 (65)

4 7 16 true -2 (74)

3 8 9 true -3 (83)

2 9 4 true -4 (92)

1 10 1 true -5 (101)


94 FLOWR Semantics


10 1 100 false 4 (110)

9 2 81 false 3 (29)

8 3 64 false 2 (38)


8 3 64 false 2 (38)

7 4 49 false 1 (47)

6 5 36 true 0 (56)

5 6 25 true -1 (65)

4 7 16 true -2 (74)

3 8 9 true -3 (83)

2 9 4 true -4 (92)

1 10 1 true -5 (101)


94 FLOWR Semantics


1 10 1 true -5 (101)

2 9 4 true -4 (92)

3 8 9 true -3 (83)


(1019283746556)



3 8 9 true -3 (83)

4 7 16 true -2 (74)

5 6 25 true -1 (65)

6 5 36 true 0 (56)


94 FLOWR Semantics


let $y = $x $x

where $y lt= 42

order by 5 - $p

return ($p$x)

$x $p $y

10 1 100



return ($p$x) 10 1 100

9 2 81

8 3 64

7 4 49

6 5 36

5 6 25

4 7 16

3 8 9

2 9 4

1 10 1


3 Prune tuples

94 FLOWR Semantics

$x $p $y where

10 1 100 false

9 2 81 false



8 3 64 false

7 4 49 false

6 5 36 true

5 6 25 true

4 7 16 true

3 8 9 true

2 9 4 true

1 10 1 true

$x $p $y where

6 5 36 true

5 6 25 true

4 7 16 true

3 8 9 true

2 9 4 true

1 10 1 true



94 FLOWR Semantics

$x $p $y order by

6 5 36 0

5 6 25 -1



4 7 16 -2

3 8 9 -3

2 9 4 -4

1 10 1 -5


6 5 36 6 (56)

5 6 25 5 (65)

4 7 16 4 (74)

3 8 9 3 (83)

2 9 4 2 (92)

1 10 1 1 (101)



94 FLOWR Semantics


ltxgtltygt12ltygt

ltygt10ltygt

ltygt7ltygt

let $x =

ltxgtltygt12ltygt

ltygt10ltygt

ltygt7ltygt



ltygt7ltygt

ltygt13ltygt

ltxgt

let $sum = 0

for $y in $xy


return $sum

ltygt7ltygt

ltygt13ltygt

ltxgt

for $y in $xy

return 0 + $y

91 Introduction

92 Preliminaries


9 XQuery

94 FLWOR Semantics































ndash Definition


















ltentrygt



element


$e $enode()






rArrrArrrArrrArr



















˽)



˽)


let $n = ltxgt

ltygtltzgt

ltxgtname()








ltxgt

ltygt

xyxml





ltygt

ltxgt












count(


()[1] ltxgtnode())

ndash Solution



x

text y

z








return


attribute id 1



ndash



y y


x

notnotnotnotis







let $x = ltxgt

return $x is $x

let $d = doc(uri)





let $x = ltxgt

let $y = ltygt







Solution


ndash A join query




ltagt





ltxgt

for $c in $abc



Result





ltagt





ltxgt

for $c in $abc

return ltgroupgt



ltgroupgt








larr empty group













return ltgroupgt




return ltgroupgt

ltcgt $c ltcgt


ltgroupgt

91 Introduction

92 Preliminaries


9 XQuery

94 FLWOR Semantics























[Gru08]


return fnname($a) )


return $adpath()





Reverse a sequence





[Gru08]



return $i





[Gru08]





Questions











[Gru08]


localhmm(ltagtltbgt


ltagt)





$from as xsstring

$to as xsstring)

typeswitch ($n)


[Gru08]



return

element

node-name($e)

$e( except $a)


else ()

for $c in $enode()


default return $n






Invoke xlate


foo

lty zoo=1gtbarltygt

ltxgt

foo

dArrdArrdArrdArr





foo

bar)

dArrdArrdArrdArr

ltx id=0 bar=gt

foo

lty zoo=1gtbarltygt

ltxgt



bull (namespaces)


bull (namespaces)





1 Introduction

2 XML Basics

3 Schema definition






97 Overview

uumluumluumluuml

uumluumluumluuml

uumluuml


to XML

6 SQLXML

7 XML processing


11 XML storage II


13 Systems


uumluumluumluuml

uumluuml




97 References

ndash M Scholl








97 References





bull Now or

bull Room IZ 232




or on appointment







A where clause




for $v in e1where p

return e2

equiv


then e2else ()




a[b = foo]c[2]d[e = 42]

for $a in a



for $a in a

where $ab = foo


where $p = 2


where $de = 42

return $d




In the FLWOR block


In the FLWOR block






for $x at $p in (53142)

order by $p

return $x




for $x at $p in (53142)

order by $p + $x

return $x



for $x at $p in (53142)

order by $x

return $x






ltb id=0gt42ltbgt

ltb id=1gt5ltbgt


ltb id=1gt5ltbgt

ltb id=2gt

ltb id=3gt3ltbgt

ltb id=4gt1ltbgt

ltagt



return $bid

Answer

91 Introduction

92 Preliminaries


9 XQuery

94 FLWOR Semantics






94 FLOWR Semantics









94 FLOWR Semantics


let $y = $x $x

where $y lt= 42

order by 5 - $p

return ($p$x)


10 1 100 false 4 (110)



return ($p$x) 10 1 100 false 4 (110)

9 2 81 false 3 (29)

8 3 64 false 2 (38)

7 4 49 false 1 (47)

6 5 36 true 0 (56)

5 6 25 true -1 (65)

4 7 16 true -2 (74)

3 8 9 true -3 (83)

2 9 4 true -4 (92)

1 10 1 true -5 (101)


94 FLOWR Semantics


10 1 100 false 4 (110)

9 2 81 false 3 (29)

8 3 64 false 2 (38)


8 3 64 false 2 (38)

7 4 49 false 1 (47)

6 5 36 true 0 (56)

5 6 25 true -1 (65)

4 7 16 true -2 (74)

3 8 9 true -3 (83)

2 9 4 true -4 (92)

1 10 1 true -5 (101)


94 FLOWR Semantics


1 10 1 true -5 (101)

2 9 4 true -4 (92)

3 8 9 true -3 (83)


(1019283746556)



3 8 9 true -3 (83)

4 7 16 true -2 (74)

5 6 25 true -1 (65)

6 5 36 true 0 (56)


94 FLOWR Semantics


let $y = $x $x

where $y lt= 42

order by 5 - $p

return ($p$x)

$x $p $y

10 1 100



return ($p$x) 10 1 100

9 2 81

8 3 64

7 4 49

6 5 36

5 6 25

4 7 16

3 8 9

2 9 4

1 10 1


3 Prune tuples

94 FLOWR Semantics

$x $p $y where

10 1 100 false

9 2 81 false



8 3 64 false

7 4 49 false

6 5 36 true

5 6 25 true

4 7 16 true

3 8 9 true

2 9 4 true

1 10 1 true

$x $p $y where

6 5 36 true

5 6 25 true

4 7 16 true

3 8 9 true

2 9 4 true

1 10 1 true



94 FLOWR Semantics

$x $p $y order by

6 5 36 0

5 6 25 -1



4 7 16 -2

3 8 9 -3

2 9 4 -4

1 10 1 -5


6 5 36 6 (56)

5 6 25 5 (65)

4 7 16 4 (74)

3 8 9 3 (83)

2 9 4 2 (92)

1 10 1 1 (101)



94 FLOWR Semantics


ltxgtltygt12ltygt

ltygt10ltygt

ltygt7ltygt

let $x =

ltxgtltygt12ltygt

ltygt10ltygt

ltygt7ltygt



ltygt7ltygt

ltygt13ltygt

ltxgt

let $sum = 0

for $y in $xy


return $sum

ltygt7ltygt

ltygt13ltygt

ltxgt

for $y in $xy

return 0 + $y

91 Introduction

92 Preliminaries


9 XQuery

94 FLWOR Semantics































ndash Definition


















ltentrygt



element


$e $enode()






rArrrArrrArrrArr



















˽)



˽)


let $n = ltxgt

ltygtltzgt

ltxgtname()








ltxgt

ltygt

xyxml





ltygt

ltxgt












count(


()[1] ltxgtnode())

ndash Solution



x

text y

z








return


attribute id 1



ndash



y y


x

notnotnotnotis







let $x = ltxgt

return $x is $x

let $d = doc(uri)





let $x = ltxgt

let $y = ltygt







Solution


ndash A join query




ltagt





ltxgt

for $c in $abc



Result





ltagt





ltxgt

for $c in $abc

return ltgroupgt



ltgroupgt








larr empty group













return ltgroupgt




return ltgroupgt

ltcgt $c ltcgt


ltgroupgt

91 Introduction

92 Preliminaries


9 XQuery

94 FLWOR Semantics























[Gru08]


return fnname($a) )


return $adpath()





Reverse a sequence





[Gru08]



return $i





[Gru08]





Questions











[Gru08]


localhmm(ltagtltbgt


ltagt)





$from as xsstring

$to as xsstring)

typeswitch ($n)


[Gru08]



return

element

node-name($e)

$e( except $a)


else ()

for $c in $enode()


default return $n






Invoke xlate


foo

lty zoo=1gtbarltygt

ltxgt

foo

dArrdArrdArrdArr





foo

bar)

dArrdArrdArrdArr

ltx id=0 bar=gt

foo

lty zoo=1gtbarltygt

ltxgt



bull (namespaces)


bull (namespaces)





1 Introduction

2 XML Basics

3 Schema definition






97 Overview

uumluumluumluuml

uumluumluumluuml

uumluuml


to XML

6 SQLXML

7 XML processing


11 XML storage II


13 Systems


uumluumluumluuml

uumluuml




97 References

ndash M Scholl








97 References





bull Now or

bull Room IZ 232




or on appointment






a[b = foo]c[2]d[e = 42]

for $a in a



for $a in a

where $ab = foo


where $p = 2


where $de = 42

return $d




In the FLWOR block


In the FLWOR block






for $x at $p in (53142)

order by $p

return $x




for $x at $p in (53142)

order by $p + $x

return $x



for $x at $p in (53142)

order by $x

return $x






ltb id=0gt42ltbgt

ltb id=1gt5ltbgt


ltb id=1gt5ltbgt

ltb id=2gt

ltb id=3gt3ltbgt

ltb id=4gt1ltbgt

ltagt



return $bid

Answer

91 Introduction

92 Preliminaries


9 XQuery

94 FLWOR Semantics






94 FLOWR Semantics









94 FLOWR Semantics


let $y = $x $x

where $y lt= 42

order by 5 - $p

return ($p$x)


10 1 100 false 4 (110)



return ($p$x) 10 1 100 false 4 (110)

9 2 81 false 3 (29)

8 3 64 false 2 (38)

7 4 49 false 1 (47)

6 5 36 true 0 (56)

5 6 25 true -1 (65)

4 7 16 true -2 (74)

3 8 9 true -3 (83)

2 9 4 true -4 (92)

1 10 1 true -5 (101)


94 FLOWR Semantics


10 1 100 false 4 (110)

9 2 81 false 3 (29)

8 3 64 false 2 (38)


8 3 64 false 2 (38)

7 4 49 false 1 (47)

6 5 36 true 0 (56)

5 6 25 true -1 (65)

4 7 16 true -2 (74)

3 8 9 true -3 (83)

2 9 4 true -4 (92)

1 10 1 true -5 (101)


94 FLOWR Semantics


1 10 1 true -5 (101)

2 9 4 true -4 (92)

3 8 9 true -3 (83)


(1019283746556)



3 8 9 true -3 (83)

4 7 16 true -2 (74)

5 6 25 true -1 (65)

6 5 36 true 0 (56)


94 FLOWR Semantics


let $y = $x $x

where $y lt= 42

order by 5 - $p

return ($p$x)

$x $p $y

10 1 100



return ($p$x) 10 1 100

9 2 81

8 3 64

7 4 49

6 5 36

5 6 25

4 7 16

3 8 9

2 9 4

1 10 1


3 Prune tuples

94 FLOWR Semantics

$x $p $y where

10 1 100 false

9 2 81 false



8 3 64 false

7 4 49 false

6 5 36 true

5 6 25 true

4 7 16 true

3 8 9 true

2 9 4 true

1 10 1 true

$x $p $y where

6 5 36 true

5 6 25 true

4 7 16 true

3 8 9 true

2 9 4 true

1 10 1 true



94 FLOWR Semantics

$x $p $y order by

6 5 36 0

5 6 25 -1



4 7 16 -2

3 8 9 -3

2 9 4 -4

1 10 1 -5


6 5 36 6 (56)

5 6 25 5 (65)

4 7 16 4 (74)

3 8 9 3 (83)

2 9 4 2 (92)

1 10 1 1 (101)



94 FLOWR Semantics


ltxgtltygt12ltygt

ltygt10ltygt

ltygt7ltygt

let $x =

ltxgtltygt12ltygt

ltygt10ltygt

ltygt7ltygt



ltygt7ltygt

ltygt13ltygt

ltxgt

let $sum = 0

for $y in $xy


return $sum

ltygt7ltygt

ltygt13ltygt

ltxgt

for $y in $xy

return 0 + $y

91 Introduction

92 Preliminaries


9 XQuery

94 FLWOR Semantics































ndash Definition


















ltentrygt



element


$e $enode()






rArrrArrrArrrArr



















˽)



˽)


let $n = ltxgt

ltygtltzgt

ltxgtname()








ltxgt

ltygt

xyxml





ltygt

ltxgt












count(


()[1] ltxgtnode())

ndash Solution



x

text y

z








return


attribute id 1



ndash



y y


x

notnotnotnotis







let $x = ltxgt

return $x is $x

let $d = doc(uri)





let $x = ltxgt

let $y = ltygt







Solution


ndash A join query




ltagt





ltxgt

for $c in $abc



Result





ltagt





ltxgt

for $c in $abc

return ltgroupgt



ltgroupgt








larr empty group













return ltgroupgt




return ltgroupgt

ltcgt $c ltcgt


ltgroupgt

91 Introduction

92 Preliminaries


9 XQuery

94 FLWOR Semantics























[Gru08]


return fnname($a) )


return $adpath()





Reverse a sequence





[Gru08]



return $i





[Gru08]





Questions











[Gru08]


localhmm(ltagtltbgt


ltagt)





$from as xsstring

$to as xsstring)

typeswitch ($n)


[Gru08]



return

element

node-name($e)

$e( except $a)


else ()

for $c in $enode()


default return $n






Invoke xlate


foo

lty zoo=1gtbarltygt

ltxgt

foo

dArrdArrdArrdArr





foo

bar)

dArrdArrdArrdArr

ltx id=0 bar=gt

foo

lty zoo=1gtbarltygt

ltxgt



bull (namespaces)


bull (namespaces)





1 Introduction

2 XML Basics

3 Schema definition






97 Overview

uumluumluumluuml

uumluumluumluuml

uumluuml


to XML

6 SQLXML

7 XML processing


11 XML storage II


13 Systems


uumluumluumluuml

uumluuml




97 References

ndash M Scholl








97 References





bull Now or

bull Room IZ 232




or on appointment






In the FLWOR block


In the FLWOR block






for $x at $p in (53142)

order by $p

return $x




for $x at $p in (53142)

order by $p + $x

return $x



for $x at $p in (53142)

order by $x

return $x






ltb id=0gt42ltbgt

ltb id=1gt5ltbgt


ltb id=1gt5ltbgt

ltb id=2gt

ltb id=3gt3ltbgt

ltb id=4gt1ltbgt

ltagt



return $bid

Answer

91 Introduction

92 Preliminaries


9 XQuery

94 FLWOR Semantics






94 FLOWR Semantics









94 FLOWR Semantics


let $y = $x $x

where $y lt= 42

order by 5 - $p

return ($p$x)


10 1 100 false 4 (110)



return ($p$x) 10 1 100 false 4 (110)

9 2 81 false 3 (29)

8 3 64 false 2 (38)

7 4 49 false 1 (47)

6 5 36 true 0 (56)

5 6 25 true -1 (65)

4 7 16 true -2 (74)

3 8 9 true -3 (83)

2 9 4 true -4 (92)

1 10 1 true -5 (101)


94 FLOWR Semantics


10 1 100 false 4 (110)

9 2 81 false 3 (29)

8 3 64 false 2 (38)


8 3 64 false 2 (38)

7 4 49 false 1 (47)

6 5 36 true 0 (56)

5 6 25 true -1 (65)

4 7 16 true -2 (74)

3 8 9 true -3 (83)

2 9 4 true -4 (92)

1 10 1 true -5 (101)


94 FLOWR Semantics


1 10 1 true -5 (101)

2 9 4 true -4 (92)

3 8 9 true -3 (83)


(1019283746556)



3 8 9 true -3 (83)

4 7 16 true -2 (74)

5 6 25 true -1 (65)

6 5 36 true 0 (56)


94 FLOWR Semantics


let $y = $x $x

where $y lt= 42

order by 5 - $p

return ($p$x)

$x $p $y

10 1 100



return ($p$x) 10 1 100

9 2 81

8 3 64

7 4 49

6 5 36

5 6 25

4 7 16

3 8 9

2 9 4

1 10 1


3 Prune tuples

94 FLOWR Semantics

$x $p $y where

10 1 100 false

9 2 81 false



8 3 64 false

7 4 49 false

6 5 36 true

5 6 25 true

4 7 16 true

3 8 9 true

2 9 4 true

1 10 1 true

$x $p $y where

6 5 36 true

5 6 25 true

4 7 16 true

3 8 9 true

2 9 4 true

1 10 1 true



94 FLOWR Semantics

$x $p $y order by

6 5 36 0

5 6 25 -1



4 7 16 -2

3 8 9 -3

2 9 4 -4

1 10 1 -5


6 5 36 6 (56)

5 6 25 5 (65)

4 7 16 4 (74)

3 8 9 3 (83)

2 9 4 2 (92)

1 10 1 1 (101)



94 FLOWR Semantics


ltxgtltygt12ltygt

ltygt10ltygt

ltygt7ltygt

let $x =

ltxgtltygt12ltygt

ltygt10ltygt

ltygt7ltygt



ltygt7ltygt

ltygt13ltygt

ltxgt

let $sum = 0

for $y in $xy


return $sum

ltygt7ltygt

ltygt13ltygt

ltxgt

for $y in $xy

return 0 + $y

91 Introduction

92 Preliminaries


9 XQuery

94 FLWOR Semantics































ndash Definition


















ltentrygt



element


$e $enode()






rArrrArrrArrrArr



















˽)



˽)


let $n = ltxgt

ltygtltzgt

ltxgtname()








ltxgt

ltygt

xyxml





ltygt

ltxgt












count(


()[1] ltxgtnode())

ndash Solution



x

text y

z








return


attribute id 1



ndash



y y


x

notnotnotnotis







let $x = ltxgt

return $x is $x

let $d = doc(uri)





let $x = ltxgt

let $y = ltygt







Solution


ndash A join query




ltagt





ltxgt

for $c in $abc



Result





ltagt





ltxgt

for $c in $abc

return ltgroupgt



ltgroupgt








larr empty group













return ltgroupgt




return ltgroupgt

ltcgt $c ltcgt


ltgroupgt

91 Introduction

92 Preliminaries


9 XQuery

94 FLWOR Semantics























[Gru08]


return fnname($a) )


return $adpath()





Reverse a sequence





[Gru08]



return $i





[Gru08]





Questions











[Gru08]


localhmm(ltagtltbgt


ltagt)





$from as xsstring

$to as xsstring)

typeswitch ($n)


[Gru08]



return

element

node-name($e)

$e( except $a)


else ()

for $c in $enode()


default return $n






Invoke xlate


foo

lty zoo=1gtbarltygt

ltxgt

foo

dArrdArrdArrdArr





foo

bar)

dArrdArrdArrdArr

ltx id=0 bar=gt

foo

lty zoo=1gtbarltygt

ltxgt



bull (namespaces)


bull (namespaces)





1 Introduction

2 XML Basics

3 Schema definition






97 Overview

uumluumluumluuml

uumluumluumluuml

uumluuml


to XML

6 SQLXML

7 XML processing


11 XML storage II


13 Systems


uumluumluumluuml

uumluuml




97 References

ndash M Scholl








97 References





bull Now or

bull Room IZ 232




or on appointment






for $x at $p in (53142)

order by $p

return $x




for $x at $p in (53142)

order by $p + $x

return $x



for $x at $p in (53142)

order by $x

return $x






ltb id=0gt42ltbgt

ltb id=1gt5ltbgt


ltb id=1gt5ltbgt

ltb id=2gt

ltb id=3gt3ltbgt

ltb id=4gt1ltbgt

ltagt



return $bid

Answer

91 Introduction

92 Preliminaries


9 XQuery

94 FLWOR Semantics






94 FLOWR Semantics









94 FLOWR Semantics


let $y = $x $x

where $y lt= 42

order by 5 - $p

return ($p$x)


10 1 100 false 4 (110)



return ($p$x) 10 1 100 false 4 (110)

9 2 81 false 3 (29)

8 3 64 false 2 (38)

7 4 49 false 1 (47)

6 5 36 true 0 (56)

5 6 25 true -1 (65)

4 7 16 true -2 (74)

3 8 9 true -3 (83)

2 9 4 true -4 (92)

1 10 1 true -5 (101)


94 FLOWR Semantics


10 1 100 false 4 (110)

9 2 81 false 3 (29)

8 3 64 false 2 (38)


8 3 64 false 2 (38)

7 4 49 false 1 (47)

6 5 36 true 0 (56)

5 6 25 true -1 (65)

4 7 16 true -2 (74)

3 8 9 true -3 (83)

2 9 4 true -4 (92)

1 10 1 true -5 (101)


94 FLOWR Semantics


1 10 1 true -5 (101)

2 9 4 true -4 (92)

3 8 9 true -3 (83)


(1019283746556)



3 8 9 true -3 (83)

4 7 16 true -2 (74)

5 6 25 true -1 (65)

6 5 36 true 0 (56)


94 FLOWR Semantics


let $y = $x $x

where $y lt= 42

order by 5 - $p

return ($p$x)

$x $p $y

10 1 100



return ($p$x) 10 1 100

9 2 81

8 3 64

7 4 49

6 5 36

5 6 25

4 7 16

3 8 9

2 9 4

1 10 1


3 Prune tuples

94 FLOWR Semantics

$x $p $y where

10 1 100 false

9 2 81 false



8 3 64 false

7 4 49 false

6 5 36 true

5 6 25 true

4 7 16 true

3 8 9 true

2 9 4 true

1 10 1 true

$x $p $y where

6 5 36 true

5 6 25 true

4 7 16 true

3 8 9 true

2 9 4 true

1 10 1 true



94 FLOWR Semantics

$x $p $y order by

6 5 36 0

5 6 25 -1



4 7 16 -2

3 8 9 -3

2 9 4 -4

1 10 1 -5


6 5 36 6 (56)

5 6 25 5 (65)

4 7 16 4 (74)

3 8 9 3 (83)

2 9 4 2 (92)

1 10 1 1 (101)



94 FLOWR Semantics


ltxgtltygt12ltygt

ltygt10ltygt

ltygt7ltygt

let $x =

ltxgtltygt12ltygt

ltygt10ltygt

ltygt7ltygt



ltygt7ltygt

ltygt13ltygt

ltxgt

let $sum = 0

for $y in $xy


return $sum

ltygt7ltygt

ltygt13ltygt

ltxgt

for $y in $xy

return 0 + $y

91 Introduction

92 Preliminaries


9 XQuery

94 FLWOR Semantics































ndash Definition


















ltentrygt



element


$e $enode()






rArrrArrrArrrArr



















˽)



˽)


let $n = ltxgt

ltygtltzgt

ltxgtname()








ltxgt

ltygt

xyxml





ltygt

ltxgt












count(


()[1] ltxgtnode())

ndash Solution



x

text y

z








return


attribute id 1



ndash



y y


x

notnotnotnotis







let $x = ltxgt

return $x is $x

let $d = doc(uri)





let $x = ltxgt

let $y = ltygt







Solution


ndash A join query




ltagt





ltxgt

for $c in $abc



Result





ltagt





ltxgt

for $c in $abc

return ltgroupgt



ltgroupgt








larr empty group













return ltgroupgt




return ltgroupgt

ltcgt $c ltcgt


ltgroupgt

91 Introduction

92 Preliminaries


9 XQuery

94 FLWOR Semantics























[Gru08]


return fnname($a) )


return $adpath()





Reverse a sequence





[Gru08]



return $i





[Gru08]





Questions











[Gru08]


localhmm(ltagtltbgt


ltagt)





$from as xsstring

$to as xsstring)

typeswitch ($n)


[Gru08]



return

element

node-name($e)

$e( except $a)


else ()

for $c in $enode()


default return $n






Invoke xlate


foo

lty zoo=1gtbarltygt

ltxgt

foo

dArrdArrdArrdArr





foo

bar)

dArrdArrdArrdArr

ltx id=0 bar=gt

foo

lty zoo=1gtbarltygt

ltxgt



bull (namespaces)


bull (namespaces)





1 Introduction

2 XML Basics

3 Schema definition






97 Overview

uumluumluumluuml

uumluumluumluuml

uumluuml


to XML

6 SQLXML

7 XML processing


11 XML storage II


13 Systems


uumluumluumluuml

uumluuml




97 References

ndash M Scholl








97 References





bull Now or

bull Room IZ 232




or on appointment







ltb id=0gt42ltbgt

ltb id=1gt5ltbgt


ltb id=1gt5ltbgt

ltb id=2gt

ltb id=3gt3ltbgt

ltb id=4gt1ltbgt

ltagt



return $bid

Answer

91 Introduction

92 Preliminaries


9 XQuery

94 FLWOR Semantics






94 FLOWR Semantics









94 FLOWR Semantics


let $y = $x $x

where $y lt= 42

order by 5 - $p

return ($p$x)


10 1 100 false 4 (110)



return ($p$x) 10 1 100 false 4 (110)

9 2 81 false 3 (29)

8 3 64 false 2 (38)

7 4 49 false 1 (47)

6 5 36 true 0 (56)

5 6 25 true -1 (65)

4 7 16 true -2 (74)

3 8 9 true -3 (83)

2 9 4 true -4 (92)

1 10 1 true -5 (101)


94 FLOWR Semantics


10 1 100 false 4 (110)

9 2 81 false 3 (29)

8 3 64 false 2 (38)


8 3 64 false 2 (38)

7 4 49 false 1 (47)

6 5 36 true 0 (56)

5 6 25 true -1 (65)

4 7 16 true -2 (74)

3 8 9 true -3 (83)

2 9 4 true -4 (92)

1 10 1 true -5 (101)


94 FLOWR Semantics


1 10 1 true -5 (101)

2 9 4 true -4 (92)

3 8 9 true -3 (83)


(1019283746556)



3 8 9 true -3 (83)

4 7 16 true -2 (74)

5 6 25 true -1 (65)

6 5 36 true 0 (56)


94 FLOWR Semantics


let $y = $x $x

where $y lt= 42

order by 5 - $p

return ($p$x)

$x $p $y

10 1 100



return ($p$x) 10 1 100

9 2 81

8 3 64

7 4 49

6 5 36

5 6 25

4 7 16

3 8 9

2 9 4

1 10 1


3 Prune tuples

94 FLOWR Semantics

$x $p $y where

10 1 100 false

9 2 81 false



8 3 64 false

7 4 49 false

6 5 36 true

5 6 25 true

4 7 16 true

3 8 9 true

2 9 4 true

1 10 1 true

$x $p $y where

6 5 36 true

5 6 25 true

4 7 16 true

3 8 9 true

2 9 4 true

1 10 1 true



94 FLOWR Semantics

$x $p $y order by

6 5 36 0

5 6 25 -1



4 7 16 -2

3 8 9 -3

2 9 4 -4

1 10 1 -5


6 5 36 6 (56)

5 6 25 5 (65)

4 7 16 4 (74)

3 8 9 3 (83)

2 9 4 2 (92)

1 10 1 1 (101)



94 FLOWR Semantics


ltxgtltygt12ltygt

ltygt10ltygt

ltygt7ltygt

let $x =

ltxgtltygt12ltygt

ltygt10ltygt

ltygt7ltygt



ltygt7ltygt

ltygt13ltygt

ltxgt

let $sum = 0

for $y in $xy


return $sum

ltygt7ltygt

ltygt13ltygt

ltxgt

for $y in $xy

return 0 + $y

91 Introduction

92 Preliminaries


9 XQuery

94 FLWOR Semantics































ndash Definition


















ltentrygt



element


$e $enode()






rArrrArrrArrrArr



















˽)



˽)


let $n = ltxgt

ltygtltzgt

ltxgtname()








ltxgt

ltygt

xyxml





ltygt

ltxgt












count(


()[1] ltxgtnode())

ndash Solution



x

text y

z








return


attribute id 1



ndash



y y


x

notnotnotnotis







let $x = ltxgt

return $x is $x

let $d = doc(uri)





let $x = ltxgt

let $y = ltygt







Solution


ndash A join query




ltagt





ltxgt

for $c in $abc



Result





ltagt





ltxgt

for $c in $abc

return ltgroupgt



ltgroupgt








larr empty group













return ltgroupgt




return ltgroupgt

ltcgt $c ltcgt


ltgroupgt

91 Introduction

92 Preliminaries


9 XQuery

94 FLWOR Semantics























[Gru08]


return fnname($a) )


return $adpath()





Reverse a sequence





[Gru08]



return $i





[Gru08]





Questions











[Gru08]


localhmm(ltagtltbgt


ltagt)





$from as xsstring

$to as xsstring)

typeswitch ($n)


[Gru08]



return

element

node-name($e)

$e( except $a)


else ()

for $c in $enode()


default return $n






Invoke xlate


foo

lty zoo=1gtbarltygt

ltxgt

foo

dArrdArrdArrdArr





foo

bar)

dArrdArrdArrdArr

ltx id=0 bar=gt

foo

lty zoo=1gtbarltygt

ltxgt



bull (namespaces)


bull (namespaces)





1 Introduction

2 XML Basics

3 Schema definition






97 Overview

uumluumluumluuml

uumluumluumluuml

uumluuml


to XML

6 SQLXML

7 XML processing


11 XML storage II


13 Systems


uumluumluumluuml

uumluuml




97 References

ndash M Scholl








97 References





bull Now or

bull Room IZ 232




or on appointment



91 Introduction

92 Preliminaries


9 XQuery

94 FLWOR Semantics






94 FLOWR Semantics









94 FLOWR Semantics


let $y = $x $x

where $y lt= 42

order by 5 - $p

return ($p$x)


10 1 100 false 4 (110)



return ($p$x) 10 1 100 false 4 (110)

9 2 81 false 3 (29)

8 3 64 false 2 (38)

7 4 49 false 1 (47)

6 5 36 true 0 (56)

5 6 25 true -1 (65)

4 7 16 true -2 (74)

3 8 9 true -3 (83)

2 9 4 true -4 (92)

1 10 1 true -5 (101)


94 FLOWR Semantics


10 1 100 false 4 (110)

9 2 81 false 3 (29)

8 3 64 false 2 (38)


8 3 64 false 2 (38)

7 4 49 false 1 (47)

6 5 36 true 0 (56)

5 6 25 true -1 (65)

4 7 16 true -2 (74)

3 8 9 true -3 (83)

2 9 4 true -4 (92)

1 10 1 true -5 (101)


94 FLOWR Semantics


1 10 1 true -5 (101)

2 9 4 true -4 (92)

3 8 9 true -3 (83)


(1019283746556)



3 8 9 true -3 (83)

4 7 16 true -2 (74)

5 6 25 true -1 (65)

6 5 36 true 0 (56)


94 FLOWR Semantics


let $y = $x $x

where $y lt= 42

order by 5 - $p

return ($p$x)

$x $p $y

10 1 100



return ($p$x) 10 1 100

9 2 81

8 3 64

7 4 49

6 5 36

5 6 25

4 7 16

3 8 9

2 9 4

1 10 1


3 Prune tuples

94 FLOWR Semantics

$x $p $y where

10 1 100 false

9 2 81 false



8 3 64 false

7 4 49 false

6 5 36 true

5 6 25 true

4 7 16 true

3 8 9 true

2 9 4 true

1 10 1 true

$x $p $y where

6 5 36 true

5 6 25 true

4 7 16 true

3 8 9 true

2 9 4 true

1 10 1 true



94 FLOWR Semantics

$x $p $y order by

6 5 36 0

5 6 25 -1



4 7 16 -2

3 8 9 -3

2 9 4 -4

1 10 1 -5


6 5 36 6 (56)

5 6 25 5 (65)

4 7 16 4 (74)

3 8 9 3 (83)

2 9 4 2 (92)

1 10 1 1 (101)



94 FLOWR Semantics


ltxgtltygt12ltygt

ltygt10ltygt

ltygt7ltygt

let $x =

ltxgtltygt12ltygt

ltygt10ltygt

ltygt7ltygt



ltygt7ltygt

ltygt13ltygt

ltxgt

let $sum = 0

for $y in $xy


return $sum

ltygt7ltygt

ltygt13ltygt

ltxgt

for $y in $xy

return 0 + $y

91 Introduction

92 Preliminaries


9 XQuery

94 FLWOR Semantics































ndash Definition


















ltentrygt



element


$e $enode()






rArrrArrrArrrArr



















˽)



˽)


let $n = ltxgt

ltygtltzgt

ltxgtname()








ltxgt

ltygt

xyxml





ltygt

ltxgt












count(


()[1] ltxgtnode())

ndash Solution



x

text y

z








return


attribute id 1



ndash



y y


x

notnotnotnotis







let $x = ltxgt

return $x is $x

let $d = doc(uri)





let $x = ltxgt

let $y = ltygt







Solution


ndash A join query




ltagt





ltxgt

for $c in $abc



Result





ltagt





ltxgt

for $c in $abc

return ltgroupgt



ltgroupgt








larr empty group













return ltgroupgt




return ltgroupgt

ltcgt $c ltcgt


ltgroupgt

91 Introduction

92 Preliminaries


9 XQuery

94 FLWOR Semantics























[Gru08]


return fnname($a) )


return $adpath()





Reverse a sequence





[Gru08]



return $i





[Gru08]





Questions











[Gru08]


localhmm(ltagtltbgt


ltagt)





$from as xsstring

$to as xsstring)

typeswitch ($n)


[Gru08]



return

element

node-name($e)

$e( except $a)


else ()

for $c in $enode()


default return $n






Invoke xlate


foo

lty zoo=1gtbarltygt

ltxgt

foo

dArrdArrdArrdArr





foo

bar)

dArrdArrdArrdArr

ltx id=0 bar=gt

foo

lty zoo=1gtbarltygt

ltxgt



bull (namespaces)


bull (namespaces)





1 Introduction

2 XML Basics

3 Schema definition






97 Overview

uumluumluumluuml

uumluumluumluuml

uumluuml


to XML

6 SQLXML

7 XML processing


11 XML storage II


13 Systems


uumluumluumluuml

uumluuml




97 References

ndash M Scholl








97 References





bull Now or

bull Room IZ 232




or on appointment




94 FLOWR Semantics









94 FLOWR Semantics


let $y = $x $x

where $y lt= 42

order by 5 - $p

return ($p$x)


10 1 100 false 4 (110)



return ($p$x) 10 1 100 false 4 (110)

9 2 81 false 3 (29)

8 3 64 false 2 (38)

7 4 49 false 1 (47)

6 5 36 true 0 (56)

5 6 25 true -1 (65)

4 7 16 true -2 (74)

3 8 9 true -3 (83)

2 9 4 true -4 (92)

1 10 1 true -5 (101)


94 FLOWR Semantics


10 1 100 false 4 (110)

9 2 81 false 3 (29)

8 3 64 false 2 (38)


8 3 64 false 2 (38)

7 4 49 false 1 (47)

6 5 36 true 0 (56)

5 6 25 true -1 (65)

4 7 16 true -2 (74)

3 8 9 true -3 (83)

2 9 4 true -4 (92)

1 10 1 true -5 (101)


94 FLOWR Semantics


1 10 1 true -5 (101)

2 9 4 true -4 (92)

3 8 9 true -3 (83)


(1019283746556)



3 8 9 true -3 (83)

4 7 16 true -2 (74)

5 6 25 true -1 (65)

6 5 36 true 0 (56)


94 FLOWR Semantics


let $y = $x $x

where $y lt= 42

order by 5 - $p

return ($p$x)

$x $p $y

10 1 100



return ($p$x) 10 1 100

9 2 81

8 3 64

7 4 49

6 5 36

5 6 25

4 7 16

3 8 9

2 9 4

1 10 1


3 Prune tuples

94 FLOWR Semantics

$x $p $y where

10 1 100 false

9 2 81 false



8 3 64 false

7 4 49 false

6 5 36 true

5 6 25 true

4 7 16 true

3 8 9 true

2 9 4 true

1 10 1 true

$x $p $y where

6 5 36 true

5 6 25 true

4 7 16 true

3 8 9 true

2 9 4 true

1 10 1 true



94 FLOWR Semantics

$x $p $y order by

6 5 36 0

5 6 25 -1



4 7 16 -2

3 8 9 -3

2 9 4 -4

1 10 1 -5


6 5 36 6 (56)

5 6 25 5 (65)

4 7 16 4 (74)

3 8 9 3 (83)

2 9 4 2 (92)

1 10 1 1 (101)



94 FLOWR Semantics


ltxgtltygt12ltygt

ltygt10ltygt

ltygt7ltygt

let $x =

ltxgtltygt12ltygt

ltygt10ltygt

ltygt7ltygt



ltygt7ltygt

ltygt13ltygt

ltxgt

let $sum = 0

for $y in $xy


return $sum

ltygt7ltygt

ltygt13ltygt

ltxgt

for $y in $xy

return 0 + $y

91 Introduction

92 Preliminaries


9 XQuery

94 FLWOR Semantics































ndash Definition


















ltentrygt



element


$e $enode()






rArrrArrrArrrArr



















˽)



˽)


let $n = ltxgt

ltygtltzgt

ltxgtname()








ltxgt

ltygt

xyxml





ltygt

ltxgt












count(


()[1] ltxgtnode())

ndash Solution



x

text y

z








return


attribute id 1



ndash



y y


x

notnotnotnotis







let $x = ltxgt

return $x is $x

let $d = doc(uri)





let $x = ltxgt

let $y = ltygt







Solution


ndash A join query




ltagt





ltxgt

for $c in $abc



Result





ltagt





ltxgt

for $c in $abc

return ltgroupgt



ltgroupgt








larr empty group













return ltgroupgt




return ltgroupgt

ltcgt $c ltcgt


ltgroupgt

91 Introduction

92 Preliminaries


9 XQuery

94 FLWOR Semantics























[Gru08]


return fnname($a) )


return $adpath()





Reverse a sequence





[Gru08]



return $i





[Gru08]





Questions











[Gru08]


localhmm(ltagtltbgt


ltagt)





$from as xsstring

$to as xsstring)

typeswitch ($n)


[Gru08]



return

element

node-name($e)

$e( except $a)


else ()

for $c in $enode()


default return $n






Invoke xlate


foo

lty zoo=1gtbarltygt

ltxgt

foo

dArrdArrdArrdArr





foo

bar)

dArrdArrdArrdArr

ltx id=0 bar=gt

foo

lty zoo=1gtbarltygt

ltxgt



bull (namespaces)


bull (namespaces)





1 Introduction

2 XML Basics

3 Schema definition






97 Overview

uumluumluumluuml

uumluumluumluuml

uumluuml


to XML

6 SQLXML

7 XML processing


11 XML storage II


13 Systems


uumluumluumluuml

uumluuml




97 References

ndash M Scholl








97 References





bull Now or

bull Room IZ 232




or on appointment




94 FLOWR Semantics


let $y = $x $x

where $y lt= 42

order by 5 - $p

return ($p$x)


10 1 100 false 4 (110)



return ($p$x) 10 1 100 false 4 (110)

9 2 81 false 3 (29)

8 3 64 false 2 (38)

7 4 49 false 1 (47)

6 5 36 true 0 (56)

5 6 25 true -1 (65)

4 7 16 true -2 (74)

3 8 9 true -3 (83)

2 9 4 true -4 (92)

1 10 1 true -5 (101)


94 FLOWR Semantics


10 1 100 false 4 (110)

9 2 81 false 3 (29)

8 3 64 false 2 (38)


8 3 64 false 2 (38)

7 4 49 false 1 (47)

6 5 36 true 0 (56)

5 6 25 true -1 (65)

4 7 16 true -2 (74)

3 8 9 true -3 (83)

2 9 4 true -4 (92)

1 10 1 true -5 (101)


94 FLOWR Semantics


1 10 1 true -5 (101)

2 9 4 true -4 (92)

3 8 9 true -3 (83)


(1019283746556)



3 8 9 true -3 (83)

4 7 16 true -2 (74)

5 6 25 true -1 (65)

6 5 36 true 0 (56)


94 FLOWR Semantics


let $y = $x $x

where $y lt= 42

order by 5 - $p

return ($p$x)

$x $p $y

10 1 100



return ($p$x) 10 1 100

9 2 81

8 3 64

7 4 49

6 5 36

5 6 25

4 7 16

3 8 9

2 9 4

1 10 1


3 Prune tuples

94 FLOWR Semantics

$x $p $y where

10 1 100 false

9 2 81 false



8 3 64 false

7 4 49 false

6 5 36 true

5 6 25 true

4 7 16 true

3 8 9 true

2 9 4 true

1 10 1 true

$x $p $y where

6 5 36 true

5 6 25 true

4 7 16 true

3 8 9 true

2 9 4 true

1 10 1 true



94 FLOWR Semantics

$x $p $y order by

6 5 36 0

5 6 25 -1



4 7 16 -2

3 8 9 -3

2 9 4 -4

1 10 1 -5


6 5 36 6 (56)

5 6 25 5 (65)

4 7 16 4 (74)

3 8 9 3 (83)

2 9 4 2 (92)

1 10 1 1 (101)



94 FLOWR Semantics


ltxgtltygt12ltygt

ltygt10ltygt

ltygt7ltygt

let $x =

ltxgtltygt12ltygt

ltygt10ltygt

ltygt7ltygt



ltygt7ltygt

ltygt13ltygt

ltxgt

let $sum = 0

for $y in $xy


return $sum

ltygt7ltygt

ltygt13ltygt

ltxgt

for $y in $xy

return 0 + $y

91 Introduction

92 Preliminaries


9 XQuery

94 FLWOR Semantics































ndash Definition


















ltentrygt



element


$e $enode()






rArrrArrrArrrArr



















˽)



˽)


let $n = ltxgt

ltygtltzgt

ltxgtname()








ltxgt

ltygt

xyxml





ltygt

ltxgt












count(


()[1] ltxgtnode())

ndash Solution



x

text y

z








return


attribute id 1



ndash



y y


x

notnotnotnotis







let $x = ltxgt

return $x is $x

let $d = doc(uri)





let $x = ltxgt

let $y = ltygt







Solution


ndash A join query




ltagt





ltxgt

for $c in $abc



Result





ltagt





ltxgt

for $c in $abc

return ltgroupgt



ltgroupgt








larr empty group













return ltgroupgt




return ltgroupgt

ltcgt $c ltcgt


ltgroupgt

91 Introduction

92 Preliminaries


9 XQuery

94 FLWOR Semantics























[Gru08]


return fnname($a) )


return $adpath()





Reverse a sequence





[Gru08]



return $i





[Gru08]





Questions











[Gru08]


localhmm(ltagtltbgt


ltagt)





$from as xsstring

$to as xsstring)

typeswitch ($n)


[Gru08]



return

element

node-name($e)

$e( except $a)


else ()

for $c in $enode()


default return $n






Invoke xlate


foo

lty zoo=1gtbarltygt

ltxgt

foo

dArrdArrdArrdArr





foo

bar)

dArrdArrdArrdArr

ltx id=0 bar=gt

foo

lty zoo=1gtbarltygt

ltxgt



bull (namespaces)


bull (namespaces)





1 Introduction

2 XML Basics

3 Schema definition






97 Overview

uumluumluumluuml

uumluumluumluuml

uumluuml


to XML

6 SQLXML

7 XML processing


11 XML storage II


13 Systems


uumluumluumluuml

uumluuml




97 References

ndash M Scholl








97 References





bull Now or

bull Room IZ 232




or on appointment




94 FLOWR Semantics


10 1 100 false 4 (110)

9 2 81 false 3 (29)

8 3 64 false 2 (38)


8 3 64 false 2 (38)

7 4 49 false 1 (47)

6 5 36 true 0 (56)

5 6 25 true -1 (65)

4 7 16 true -2 (74)

3 8 9 true -3 (83)

2 9 4 true -4 (92)

1 10 1 true -5 (101)


94 FLOWR Semantics


1 10 1 true -5 (101)

2 9 4 true -4 (92)

3 8 9 true -3 (83)


(1019283746556)



3 8 9 true -3 (83)

4 7 16 true -2 (74)

5 6 25 true -1 (65)

6 5 36 true 0 (56)


94 FLOWR Semantics


let $y = $x $x

where $y lt= 42

order by 5 - $p

return ($p$x)

$x $p $y

10 1 100



return ($p$x) 10 1 100

9 2 81

8 3 64

7 4 49

6 5 36

5 6 25

4 7 16

3 8 9

2 9 4

1 10 1


3 Prune tuples

94 FLOWR Semantics

$x $p $y where

10 1 100 false

9 2 81 false



8 3 64 false

7 4 49 false

6 5 36 true

5 6 25 true

4 7 16 true

3 8 9 true

2 9 4 true

1 10 1 true

$x $p $y where

6 5 36 true

5 6 25 true

4 7 16 true

3 8 9 true

2 9 4 true

1 10 1 true



94 FLOWR Semantics

$x $p $y order by

6 5 36 0

5 6 25 -1



4 7 16 -2

3 8 9 -3

2 9 4 -4

1 10 1 -5


6 5 36 6 (56)

5 6 25 5 (65)

4 7 16 4 (74)

3 8 9 3 (83)

2 9 4 2 (92)

1 10 1 1 (101)



94 FLOWR Semantics


ltxgtltygt12ltygt

ltygt10ltygt

ltygt7ltygt

let $x =

ltxgtltygt12ltygt

ltygt10ltygt

ltygt7ltygt



ltygt7ltygt

ltygt13ltygt

ltxgt

let $sum = 0

for $y in $xy


return $sum

ltygt7ltygt

ltygt13ltygt

ltxgt

for $y in $xy

return 0 + $y

91 Introduction

92 Preliminaries


9 XQuery

94 FLWOR Semantics































ndash Definition


















ltentrygt



element


$e $enode()






rArrrArrrArrrArr



















˽)



˽)


let $n = ltxgt

ltygtltzgt

ltxgtname()








ltxgt

ltygt

xyxml





ltygt

ltxgt












count(


()[1] ltxgtnode())

ndash Solution



x

text y

z








return


attribute id 1



ndash



y y


x

notnotnotnotis







let $x = ltxgt

return $x is $x

let $d = doc(uri)





let $x = ltxgt

let $y = ltygt







Solution


ndash A join query




ltagt





ltxgt

for $c in $abc



Result





ltagt





ltxgt

for $c in $abc

return ltgroupgt



ltgroupgt








larr empty group













return ltgroupgt




return ltgroupgt

ltcgt $c ltcgt


ltgroupgt

91 Introduction

92 Preliminaries


9 XQuery

94 FLWOR Semantics























[Gru08]


return fnname($a) )


return $adpath()





Reverse a sequence





[Gru08]



return $i





[Gru08]





Questions











[Gru08]


localhmm(ltagtltbgt


ltagt)





$from as xsstring

$to as xsstring)

typeswitch ($n)


[Gru08]



return

element

node-name($e)

$e( except $a)


else ()

for $c in $enode()


default return $n






Invoke xlate


foo

lty zoo=1gtbarltygt

ltxgt

foo

dArrdArrdArrdArr





foo

bar)

dArrdArrdArrdArr

ltx id=0 bar=gt

foo

lty zoo=1gtbarltygt

ltxgt



bull (namespaces)


bull (namespaces)





1 Introduction

2 XML Basics

3 Schema definition






97 Overview

uumluumluumluuml

uumluumluumluuml

uumluuml


to XML

6 SQLXML

7 XML processing


11 XML storage II


13 Systems


uumluumluumluuml

uumluuml




97 References

ndash M Scholl








97 References





bull Now or

bull Room IZ 232




or on appointment




94 FLOWR Semantics


1 10 1 true -5 (101)

2 9 4 true -4 (92)

3 8 9 true -3 (83)


(1019283746556)



3 8 9 true -3 (83)

4 7 16 true -2 (74)

5 6 25 true -1 (65)

6 5 36 true 0 (56)


94 FLOWR Semantics


let $y = $x $x

where $y lt= 42

order by 5 - $p

return ($p$x)

$x $p $y

10 1 100



return ($p$x) 10 1 100

9 2 81

8 3 64

7 4 49

6 5 36

5 6 25

4 7 16

3 8 9

2 9 4

1 10 1


3 Prune tuples

94 FLOWR Semantics

$x $p $y where

10 1 100 false

9 2 81 false



8 3 64 false

7 4 49 false

6 5 36 true

5 6 25 true

4 7 16 true

3 8 9 true

2 9 4 true

1 10 1 true

$x $p $y where

6 5 36 true

5 6 25 true

4 7 16 true

3 8 9 true

2 9 4 true

1 10 1 true



94 FLOWR Semantics

$x $p $y order by

6 5 36 0

5 6 25 -1



4 7 16 -2

3 8 9 -3

2 9 4 -4

1 10 1 -5


6 5 36 6 (56)

5 6 25 5 (65)

4 7 16 4 (74)

3 8 9 3 (83)

2 9 4 2 (92)

1 10 1 1 (101)



94 FLOWR Semantics


ltxgtltygt12ltygt

ltygt10ltygt

ltygt7ltygt

let $x =

ltxgtltygt12ltygt

ltygt10ltygt

ltygt7ltygt



ltygt7ltygt

ltygt13ltygt

ltxgt

let $sum = 0

for $y in $xy


return $sum

ltygt7ltygt

ltygt13ltygt

ltxgt

for $y in $xy

return 0 + $y

91 Introduction

92 Preliminaries


9 XQuery

94 FLWOR Semantics































ndash Definition


















ltentrygt



element


$e $enode()






rArrrArrrArrrArr



















˽)



˽)


let $n = ltxgt

ltygtltzgt

ltxgtname()








ltxgt

ltygt

xyxml





ltygt

ltxgt












count(


()[1] ltxgtnode())

ndash Solution



x

text y

z








return


attribute id 1



ndash



y y


x

notnotnotnotis







let $x = ltxgt

return $x is $x

let $d = doc(uri)





let $x = ltxgt

let $y = ltygt







Solution


ndash A join query




ltagt





ltxgt

for $c in $abc



Result





ltagt





ltxgt

for $c in $abc

return ltgroupgt



ltgroupgt








larr empty group













return ltgroupgt




return ltgroupgt

ltcgt $c ltcgt


ltgroupgt

91 Introduction

92 Preliminaries


9 XQuery

94 FLWOR Semantics























[Gru08]


return fnname($a) )


return $adpath()





Reverse a sequence





[Gru08]



return $i





[Gru08]





Questions











[Gru08]


localhmm(ltagtltbgt


ltagt)





$from as xsstring

$to as xsstring)

typeswitch ($n)


[Gru08]



return

element

node-name($e)

$e( except $a)


else ()

for $c in $enode()


default return $n






Invoke xlate


foo

lty zoo=1gtbarltygt

ltxgt

foo

dArrdArrdArrdArr





foo

bar)

dArrdArrdArrdArr

ltx id=0 bar=gt

foo

lty zoo=1gtbarltygt

ltxgt



bull (namespaces)


bull (namespaces)





1 Introduction

2 XML Basics

3 Schema definition






97 Overview

uumluumluumluuml

uumluumluumluuml

uumluuml


to XML

6 SQLXML

7 XML processing


11 XML storage II


13 Systems


uumluumluumluuml

uumluuml




97 References

ndash M Scholl








97 References





bull Now or

bull Room IZ 232




or on appointment




94 FLOWR Semantics


let $y = $x $x

where $y lt= 42

order by 5 - $p

return ($p$x)

$x $p $y

10 1 100



return ($p$x) 10 1 100

9 2 81

8 3 64

7 4 49

6 5 36

5 6 25

4 7 16

3 8 9

2 9 4

1 10 1


3 Prune tuples

94 FLOWR Semantics

$x $p $y where

10 1 100 false

9 2 81 false



8 3 64 false

7 4 49 false

6 5 36 true

5 6 25 true

4 7 16 true

3 8 9 true

2 9 4 true

1 10 1 true

$x $p $y where

6 5 36 true

5 6 25 true

4 7 16 true

3 8 9 true

2 9 4 true

1 10 1 true



94 FLOWR Semantics

$x $p $y order by

6 5 36 0

5 6 25 -1



4 7 16 -2

3 8 9 -3

2 9 4 -4

1 10 1 -5


6 5 36 6 (56)

5 6 25 5 (65)

4 7 16 4 (74)

3 8 9 3 (83)

2 9 4 2 (92)

1 10 1 1 (101)



94 FLOWR Semantics


ltxgtltygt12ltygt

ltygt10ltygt

ltygt7ltygt

let $x =

ltxgtltygt12ltygt

ltygt10ltygt

ltygt7ltygt



ltygt7ltygt

ltygt13ltygt

ltxgt

let $sum = 0

for $y in $xy


return $sum

ltygt7ltygt

ltygt13ltygt

ltxgt

for $y in $xy

return 0 + $y

91 Introduction

92 Preliminaries


9 XQuery

94 FLWOR Semantics































ndash Definition


















ltentrygt



element


$e $enode()






rArrrArrrArrrArr



















˽)



˽)


let $n = ltxgt

ltygtltzgt

ltxgtname()








ltxgt

ltygt

xyxml





ltygt

ltxgt












count(


()[1] ltxgtnode())

ndash Solution



x

text y

z








return


attribute id 1



ndash



y y


x

notnotnotnotis







let $x = ltxgt

return $x is $x

let $d = doc(uri)





let $x = ltxgt

let $y = ltygt







Solution


ndash A join query




ltagt





ltxgt

for $c in $abc



Result





ltagt





ltxgt

for $c in $abc

return ltgroupgt



ltgroupgt








larr empty group













return ltgroupgt




return ltgroupgt

ltcgt $c ltcgt


ltgroupgt

91 Introduction

92 Preliminaries


9 XQuery

94 FLWOR Semantics























[Gru08]


return fnname($a) )


return $adpath()





Reverse a sequence





[Gru08]



return $i





[Gru08]





Questions











[Gru08]


localhmm(ltagtltbgt


ltagt)





$from as xsstring

$to as xsstring)

typeswitch ($n)


[Gru08]



return

element

node-name($e)

$e( except $a)


else ()

for $c in $enode()


default return $n






Invoke xlate


foo

lty zoo=1gtbarltygt

ltxgt

foo

dArrdArrdArrdArr





foo

bar)

dArrdArrdArrdArr

ltx id=0 bar=gt

foo

lty zoo=1gtbarltygt

ltxgt



bull (namespaces)


bull (namespaces)





1 Introduction

2 XML Basics

3 Schema definition






97 Overview

uumluumluumluuml

uumluumluumluuml

uumluuml


to XML

6 SQLXML

7 XML processing


11 XML storage II


13 Systems


uumluumluumluuml

uumluuml




97 References

ndash M Scholl








97 References





bull Now or

bull Room IZ 232




or on appointment




3 Prune tuples

94 FLOWR Semantics

$x $p $y where

10 1 100 false

9 2 81 false



8 3 64 false

7 4 49 false

6 5 36 true

5 6 25 true

4 7 16 true

3 8 9 true

2 9 4 true

1 10 1 true

$x $p $y where

6 5 36 true

5 6 25 true

4 7 16 true

3 8 9 true

2 9 4 true

1 10 1 true



94 FLOWR Semantics

$x $p $y order by

6 5 36 0

5 6 25 -1



4 7 16 -2

3 8 9 -3

2 9 4 -4

1 10 1 -5


6 5 36 6 (56)

5 6 25 5 (65)

4 7 16 4 (74)

3 8 9 3 (83)

2 9 4 2 (92)

1 10 1 1 (101)



94 FLOWR Semantics


ltxgtltygt12ltygt

ltygt10ltygt

ltygt7ltygt

let $x =

ltxgtltygt12ltygt

ltygt10ltygt

ltygt7ltygt



ltygt7ltygt

ltygt13ltygt

ltxgt

let $sum = 0

for $y in $xy


return $sum

ltygt7ltygt

ltygt13ltygt

ltxgt

for $y in $xy

return 0 + $y

91 Introduction

92 Preliminaries


9 XQuery

94 FLWOR Semantics































ndash Definition


















ltentrygt



element


$e $enode()






rArrrArrrArrrArr



















˽)



˽)


let $n = ltxgt

ltygtltzgt

ltxgtname()








ltxgt

ltygt

xyxml





ltygt

ltxgt












count(


()[1] ltxgtnode())

ndash Solution



x

text y

z








return


attribute id 1



ndash



y y


x

notnotnotnotis







let $x = ltxgt

return $x is $x

let $d = doc(uri)





let $x = ltxgt

let $y = ltygt







Solution


ndash A join query




ltagt





ltxgt

for $c in $abc



Result





ltagt





ltxgt

for $c in $abc

return ltgroupgt



ltgroupgt








larr empty group













return ltgroupgt




return ltgroupgt

ltcgt $c ltcgt


ltgroupgt

91 Introduction

92 Preliminaries


9 XQuery

94 FLWOR Semantics























[Gru08]


return fnname($a) )


return $adpath()





Reverse a sequence





[Gru08]



return $i





[Gru08]





Questions











[Gru08]


localhmm(ltagtltbgt


ltagt)





$from as xsstring

$to as xsstring)

typeswitch ($n)


[Gru08]



return

element

node-name($e)

$e( except $a)


else ()

for $c in $enode()


default return $n






Invoke xlate


foo

lty zoo=1gtbarltygt

ltxgt

foo

dArrdArrdArrdArr





foo

bar)

dArrdArrdArrdArr

ltx id=0 bar=gt

foo

lty zoo=1gtbarltygt

ltxgt



bull (namespaces)


bull (namespaces)





1 Introduction

2 XML Basics

3 Schema definition






97 Overview

uumluumluumluuml

uumluumluumluuml

uumluuml


to XML

6 SQLXML

7 XML processing


11 XML storage II


13 Systems


uumluumluumluuml

uumluuml




97 References

ndash M Scholl








97 References





bull Now or

bull Room IZ 232




or on appointment





94 FLOWR Semantics

$x $p $y order by

6 5 36 0

5 6 25 -1



4 7 16 -2

3 8 9 -3

2 9 4 -4

1 10 1 -5


6 5 36 6 (56)

5 6 25 5 (65)

4 7 16 4 (74)

3 8 9 3 (83)

2 9 4 2 (92)

1 10 1 1 (101)



94 FLOWR Semantics


ltxgtltygt12ltygt

ltygt10ltygt

ltygt7ltygt

let $x =

ltxgtltygt12ltygt

ltygt10ltygt

ltygt7ltygt



ltygt7ltygt

ltygt13ltygt

ltxgt

let $sum = 0

for $y in $xy


return $sum

ltygt7ltygt

ltygt13ltygt

ltxgt

for $y in $xy

return 0 + $y

91 Introduction

92 Preliminaries


9 XQuery

94 FLWOR Semantics































ndash Definition


















ltentrygt



element


$e $enode()






rArrrArrrArrrArr



















˽)



˽)


let $n = ltxgt

ltygtltzgt

ltxgtname()








ltxgt

ltygt

xyxml





ltygt

ltxgt












count(


()[1] ltxgtnode())

ndash Solution



x

text y

z








return


attribute id 1



ndash



y y


x

notnotnotnotis







let $x = ltxgt

return $x is $x

let $d = doc(uri)





let $x = ltxgt

let $y = ltygt







Solution


ndash A join query




ltagt





ltxgt

for $c in $abc



Result





ltagt





ltxgt

for $c in $abc

return ltgroupgt



ltgroupgt








larr empty group













return ltgroupgt




return ltgroupgt

ltcgt $c ltcgt


ltgroupgt

91 Introduction

92 Preliminaries


9 XQuery

94 FLWOR Semantics























[Gru08]


return fnname($a) )


return $adpath()





Reverse a sequence





[Gru08]



return $i





[Gru08]





Questions











[Gru08]


localhmm(ltagtltbgt


ltagt)





$from as xsstring

$to as xsstring)

typeswitch ($n)


[Gru08]



return

element

node-name($e)

$e( except $a)


else ()

for $c in $enode()


default return $n






Invoke xlate


foo

lty zoo=1gtbarltygt

ltxgt

foo

dArrdArrdArrdArr





foo

bar)

dArrdArrdArrdArr

ltx id=0 bar=gt

foo

lty zoo=1gtbarltygt

ltxgt



bull (namespaces)


bull (namespaces)





1 Introduction

2 XML Basics

3 Schema definition






97 Overview

uumluumluumluuml

uumluumluumluuml

uumluuml


to XML

6 SQLXML

7 XML processing


11 XML storage II


13 Systems


uumluumluumluuml

uumluuml




97 References

ndash M Scholl








97 References





bull Now or

bull Room IZ 232




or on appointment





94 FLOWR Semantics


ltxgtltygt12ltygt

ltygt10ltygt

ltygt7ltygt

let $x =

ltxgtltygt12ltygt

ltygt10ltygt

ltygt7ltygt



ltygt7ltygt

ltygt13ltygt

ltxgt

let $sum = 0

for $y in $xy


return $sum

ltygt7ltygt

ltygt13ltygt

ltxgt

for $y in $xy

return 0 + $y

91 Introduction

92 Preliminaries


9 XQuery

94 FLWOR Semantics































ndash Definition


















ltentrygt



element


$e $enode()






rArrrArrrArrrArr



















˽)



˽)


let $n = ltxgt

ltygtltzgt

ltxgtname()








ltxgt

ltygt

xyxml





ltygt

ltxgt












count(


()[1] ltxgtnode())

ndash Solution



x

text y

z








return


attribute id 1



ndash



y y


x

notnotnotnotis







let $x = ltxgt

return $x is $x

let $d = doc(uri)





let $x = ltxgt

let $y = ltygt







Solution


ndash A join query




ltagt





ltxgt

for $c in $abc



Result





ltagt





ltxgt

for $c in $abc

return ltgroupgt



ltgroupgt








larr empty group













return ltgroupgt




return ltgroupgt

ltcgt $c ltcgt


ltgroupgt

91 Introduction

92 Preliminaries


9 XQuery

94 FLWOR Semantics























[Gru08]


return fnname($a) )


return $adpath()





Reverse a sequence





[Gru08]



return $i





[Gru08]





Questions











[Gru08]


localhmm(ltagtltbgt


ltagt)





$from as xsstring

$to as xsstring)

typeswitch ($n)


[Gru08]



return

element

node-name($e)

$e( except $a)


else ()

for $c in $enode()


default return $n






Invoke xlate


foo

lty zoo=1gtbarltygt

ltxgt

foo

dArrdArrdArrdArr





foo

bar)

dArrdArrdArrdArr

ltx id=0 bar=gt

foo

lty zoo=1gtbarltygt

ltxgt



bull (namespaces)


bull (namespaces)





1 Introduction

2 XML Basics

3 Schema definition






97 Overview

uumluumluumluuml

uumluumluumluuml

uumluuml


to XML

6 SQLXML

7 XML processing


11 XML storage II


13 Systems


uumluumluumluuml

uumluuml




97 References

ndash M Scholl








97 References





bull Now or

bull Room IZ 232




or on appointment



91 Introduction

92 Preliminaries


9 XQuery

94 FLWOR Semantics































ndash Definition


















ltentrygt



element


$e $enode()






rArrrArrrArrrArr



















˽)



˽)


let $n = ltxgt

ltygtltzgt

ltxgtname()








ltxgt

ltygt

xyxml





ltygt

ltxgt












count(


()[1] ltxgtnode())

ndash Solution



x

text y

z








return


attribute id 1



ndash



y y


x

notnotnotnotis







let $x = ltxgt

return $x is $x

let $d = doc(uri)





let $x = ltxgt

let $y = ltygt







Solution


ndash A join query




ltagt





ltxgt

for $c in $abc



Result





ltagt





ltxgt

for $c in $abc

return ltgroupgt



ltgroupgt








larr empty group













return ltgroupgt




return ltgroupgt

ltcgt $c ltcgt


ltgroupgt

91 Introduction

92 Preliminaries


9 XQuery

94 FLWOR Semantics























[Gru08]


return fnname($a) )


return $adpath()





Reverse a sequence





[Gru08]



return $i





[Gru08]





Questions











[Gru08]


localhmm(ltagtltbgt


ltagt)





$from as xsstring

$to as xsstring)

typeswitch ($n)


[Gru08]



return

element

node-name($e)

$e( except $a)


else ()

for $c in $enode()


default return $n






Invoke xlate


foo

lty zoo=1gtbarltygt

ltxgt

foo

dArrdArrdArrdArr





foo

bar)

dArrdArrdArrdArr

ltx id=0 bar=gt

foo

lty zoo=1gtbarltygt

ltxgt



bull (namespaces)


bull (namespaces)





1 Introduction

2 XML Basics

3 Schema definition






97 Overview

uumluumluumluuml

uumluumluumluuml

uumluuml


to XML

6 SQLXML

7 XML processing


11 XML storage II


13 Systems


uumluumluumluuml

uumluuml




97 References

ndash M Scholl








97 References





bull Now or

bull Room IZ 232




or on appointment





























ndash Definition


















ltentrygt



element


$e $enode()






rArrrArrrArrrArr



















˽)



˽)


let $n = ltxgt

ltygtltzgt

ltxgtname()








ltxgt

ltygt

xyxml





ltygt

ltxgt












count(


()[1] ltxgtnode())

ndash Solution



x

text y

z








return


attribute id 1



ndash



y y


x

notnotnotnotis







let $x = ltxgt

return $x is $x

let $d = doc(uri)





let $x = ltxgt

let $y = ltygt







Solution


ndash A join query




ltagt





ltxgt

for $c in $abc



Result





ltagt





ltxgt

for $c in $abc

return ltgroupgt



ltgroupgt








larr empty group













return ltgroupgt




return ltgroupgt

ltcgt $c ltcgt


ltgroupgt

91 Introduction

92 Preliminaries


9 XQuery

94 FLWOR Semantics























[Gru08]


return fnname($a) )


return $adpath()





Reverse a sequence





[Gru08]



return $i





[Gru08]





Questions











[Gru08]


localhmm(ltagtltbgt


ltagt)





$from as xsstring

$to as xsstring)

typeswitch ($n)


[Gru08]



return

element

node-name($e)

$e( except $a)


else ()

for $c in $enode()


default return $n






Invoke xlate


foo

lty zoo=1gtbarltygt

ltxgt

foo

dArrdArrdArrdArr





foo

bar)

dArrdArrdArrdArr

ltx id=0 bar=gt

foo

lty zoo=1gtbarltygt

ltxgt



bull (namespaces)


bull (namespaces)





1 Introduction

2 XML Basics

3 Schema definition






97 Overview

uumluumluumluuml

uumluumluumluuml

uumluuml


to XML

6 SQLXML

7 XML processing


11 XML storage II


13 Systems


uumluumluumluuml

uumluuml




97 References

ndash M Scholl








97 References





bull Now or

bull Room IZ 232




or on appointment











ltentrygt



element


$e $enode()






rArrrArrrArrrArr



















˽)



˽)


let $n = ltxgt

ltygtltzgt

ltxgtname()








ltxgt

ltygt

xyxml





ltygt

ltxgt












count(


()[1] ltxgtnode())

ndash Solution



x

text y

z








return


attribute id 1



ndash



y y


x

notnotnotnotis







let $x = ltxgt

return $x is $x

let $d = doc(uri)





let $x = ltxgt

let $y = ltygt







Solution


ndash A join query




ltagt





ltxgt

for $c in $abc



Result





ltagt





ltxgt

for $c in $abc

return ltgroupgt



ltgroupgt








larr empty group













return ltgroupgt




return ltgroupgt

ltcgt $c ltcgt


ltgroupgt

91 Introduction

92 Preliminaries


9 XQuery

94 FLWOR Semantics























[Gru08]


return fnname($a) )


return $adpath()





Reverse a sequence





[Gru08]



return $i





[Gru08]





Questions











[Gru08]


localhmm(ltagtltbgt


ltagt)





$from as xsstring

$to as xsstring)

typeswitch ($n)


[Gru08]



return

element

node-name($e)

$e( except $a)


else ()

for $c in $enode()


default return $n






Invoke xlate


foo

lty zoo=1gtbarltygt

ltxgt

foo

dArrdArrdArrdArr





foo

bar)

dArrdArrdArrdArr

ltx id=0 bar=gt

foo

lty zoo=1gtbarltygt

ltxgt



bull (namespaces)


bull (namespaces)





1 Introduction

2 XML Basics

3 Schema definition






97 Overview

uumluumluumluuml

uumluumluumluuml

uumluuml


to XML

6 SQLXML

7 XML processing


11 XML storage II


13 Systems


uumluumluumluuml

uumluuml




97 References

ndash M Scholl








97 References





bull Now or

bull Room IZ 232




or on appointment








rArrrArrrArrrArr



















˽)



˽)


let $n = ltxgt

ltygtltzgt

ltxgtname()








ltxgt

ltygt

xyxml





ltygt

ltxgt












count(


()[1] ltxgtnode())

ndash Solution



x

text y

z








return


attribute id 1



ndash



y y


x

notnotnotnotis







let $x = ltxgt

return $x is $x

let $d = doc(uri)





let $x = ltxgt

let $y = ltygt







Solution


ndash A join query




ltagt





ltxgt

for $c in $abc



Result





ltagt





ltxgt

for $c in $abc

return ltgroupgt



ltgroupgt








larr empty group













return ltgroupgt




return ltgroupgt

ltcgt $c ltcgt


ltgroupgt

91 Introduction

92 Preliminaries


9 XQuery

94 FLWOR Semantics























[Gru08]


return fnname($a) )


return $adpath()





Reverse a sequence





[Gru08]



return $i





[Gru08]





Questions











[Gru08]


localhmm(ltagtltbgt


ltagt)





$from as xsstring

$to as xsstring)

typeswitch ($n)


[Gru08]



return

element

node-name($e)

$e( except $a)


else ()

for $c in $enode()


default return $n






Invoke xlate


foo

lty zoo=1gtbarltygt

ltxgt

foo

dArrdArrdArrdArr





foo

bar)

dArrdArrdArrdArr

ltx id=0 bar=gt

foo

lty zoo=1gtbarltygt

ltxgt



bull (namespaces)


bull (namespaces)





1 Introduction

2 XML Basics

3 Schema definition






97 Overview

uumluumluumluuml

uumluumluumluuml

uumluuml


to XML

6 SQLXML

7 XML processing


11 XML storage II


13 Systems


uumluumluumluuml

uumluuml




97 References

ndash M Scholl








97 References





bull Now or

bull Room IZ 232




or on appointment














˽)



˽)


let $n = ltxgt

ltygtltzgt

ltxgtname()








ltxgt

ltygt

xyxml





ltygt

ltxgt












count(


()[1] ltxgtnode())

ndash Solution



x

text y

z








return


attribute id 1



ndash



y y


x

notnotnotnotis







let $x = ltxgt

return $x is $x

let $d = doc(uri)





let $x = ltxgt

let $y = ltygt







Solution


ndash A join query




ltagt





ltxgt

for $c in $abc



Result





ltagt





ltxgt

for $c in $abc

return ltgroupgt



ltgroupgt








larr empty group













return ltgroupgt




return ltgroupgt

ltcgt $c ltcgt


ltgroupgt

91 Introduction

92 Preliminaries


9 XQuery

94 FLWOR Semantics























[Gru08]


return fnname($a) )


return $adpath()





Reverse a sequence





[Gru08]



return $i





[Gru08]





Questions











[Gru08]


localhmm(ltagtltbgt


ltagt)





$from as xsstring

$to as xsstring)

typeswitch ($n)


[Gru08]



return

element

node-name($e)

$e( except $a)


else ()

for $c in $enode()


default return $n






Invoke xlate


foo

lty zoo=1gtbarltygt

ltxgt

foo

dArrdArrdArrdArr





foo

bar)

dArrdArrdArrdArr

ltx id=0 bar=gt

foo

lty zoo=1gtbarltygt

ltxgt



bull (namespaces)


bull (namespaces)





1 Introduction

2 XML Basics

3 Schema definition






97 Overview

uumluumluumluuml

uumluumluumluuml

uumluuml


to XML

6 SQLXML

7 XML processing


11 XML storage II


13 Systems


uumluumluumluuml

uumluuml




97 References

ndash M Scholl








97 References





bull Now or

bull Room IZ 232




or on appointment








ltxgt

ltygt

xyxml





ltygt

ltxgt












count(


()[1] ltxgtnode())

ndash Solution



x

text y

z








return


attribute id 1



ndash



y y


x

notnotnotnotis







let $x = ltxgt

return $x is $x

let $d = doc(uri)





let $x = ltxgt

let $y = ltygt







Solution


ndash A join query




ltagt





ltxgt

for $c in $abc



Result





ltagt





ltxgt

for $c in $abc

return ltgroupgt



ltgroupgt








larr empty group













return ltgroupgt




return ltgroupgt

ltcgt $c ltcgt


ltgroupgt

91 Introduction

92 Preliminaries


9 XQuery

94 FLWOR Semantics























[Gru08]


return fnname($a) )


return $adpath()





Reverse a sequence





[Gru08]



return $i





[Gru08]





Questions











[Gru08]


localhmm(ltagtltbgt


ltagt)





$from as xsstring

$to as xsstring)

typeswitch ($n)


[Gru08]



return

element

node-name($e)

$e( except $a)


else ()

for $c in $enode()


default return $n






Invoke xlate


foo

lty zoo=1gtbarltygt

ltxgt

foo

dArrdArrdArrdArr





foo

bar)

dArrdArrdArrdArr

ltx id=0 bar=gt

foo

lty zoo=1gtbarltygt

ltxgt



bull (namespaces)


bull (namespaces)





1 Introduction

2 XML Basics

3 Schema definition






97 Overview

uumluumluumluuml

uumluumluumluuml

uumluuml


to XML

6 SQLXML

7 XML processing


11 XML storage II


13 Systems


uumluumluumluuml

uumluuml




97 References

ndash M Scholl








97 References





bull Now or

bull Room IZ 232




or on appointment













count(


()[1] ltxgtnode())

ndash Solution



x

text y

z








return


attribute id 1



ndash



y y


x

notnotnotnotis







let $x = ltxgt

return $x is $x

let $d = doc(uri)





let $x = ltxgt

let $y = ltygt







Solution


ndash A join query




ltagt





ltxgt

for $c in $abc



Result





ltagt





ltxgt

for $c in $abc

return ltgroupgt



ltgroupgt








larr empty group













return ltgroupgt




return ltgroupgt

ltcgt $c ltcgt


ltgroupgt

91 Introduction

92 Preliminaries


9 XQuery

94 FLWOR Semantics























[Gru08]


return fnname($a) )


return $adpath()





Reverse a sequence





[Gru08]



return $i





[Gru08]





Questions











[Gru08]


localhmm(ltagtltbgt


ltagt)





$from as xsstring

$to as xsstring)

typeswitch ($n)


[Gru08]



return

element

node-name($e)

$e( except $a)


else ()

for $c in $enode()


default return $n






Invoke xlate


foo

lty zoo=1gtbarltygt

ltxgt

foo

dArrdArrdArrdArr





foo

bar)

dArrdArrdArrdArr

ltx id=0 bar=gt

foo

lty zoo=1gtbarltygt

ltxgt



bull (namespaces)


bull (namespaces)





1 Introduction

2 XML Basics

3 Schema definition






97 Overview

uumluumluumluuml

uumluumluumluuml

uumluuml


to XML

6 SQLXML

7 XML processing


11 XML storage II


13 Systems


uumluumluumluuml

uumluuml




97 References

ndash M Scholl








97 References





bull Now or

bull Room IZ 232




or on appointment









return


attribute id 1



ndash



y y


x

notnotnotnotis







let $x = ltxgt

return $x is $x

let $d = doc(uri)





let $x = ltxgt

let $y = ltygt







Solution


ndash A join query




ltagt





ltxgt

for $c in $abc



Result





ltagt





ltxgt

for $c in $abc

return ltgroupgt



ltgroupgt








larr empty group













return ltgroupgt




return ltgroupgt

ltcgt $c ltcgt


ltgroupgt

91 Introduction

92 Preliminaries


9 XQuery

94 FLWOR Semantics























[Gru08]


return fnname($a) )


return $adpath()





Reverse a sequence





[Gru08]



return $i





[Gru08]





Questions











[Gru08]


localhmm(ltagtltbgt


ltagt)





$from as xsstring

$to as xsstring)

typeswitch ($n)


[Gru08]



return

element

node-name($e)

$e( except $a)


else ()

for $c in $enode()


default return $n






Invoke xlate


foo

lty zoo=1gtbarltygt

ltxgt

foo

dArrdArrdArrdArr





foo

bar)

dArrdArrdArrdArr

ltx id=0 bar=gt

foo

lty zoo=1gtbarltygt

ltxgt



bull (namespaces)


bull (namespaces)





1 Introduction

2 XML Basics

3 Schema definition






97 Overview

uumluumluumluuml

uumluumluumluuml

uumluuml


to XML

6 SQLXML

7 XML processing


11 XML storage II


13 Systems


uumluumluumluuml

uumluuml




97 References

ndash M Scholl








97 References





bull Now or

bull Room IZ 232




or on appointment




ndash



y y


x

notnotnotnotis







let $x = ltxgt

return $x is $x

let $d = doc(uri)





let $x = ltxgt

let $y = ltygt







Solution


ndash A join query




ltagt





ltxgt

for $c in $abc



Result





ltagt





ltxgt

for $c in $abc

return ltgroupgt



ltgroupgt








larr empty group













return ltgroupgt




return ltgroupgt

ltcgt $c ltcgt


ltgroupgt

91 Introduction

92 Preliminaries


9 XQuery

94 FLWOR Semantics























[Gru08]


return fnname($a) )


return $adpath()





Reverse a sequence





[Gru08]



return $i





[Gru08]





Questions











[Gru08]


localhmm(ltagtltbgt


ltagt)





$from as xsstring

$to as xsstring)

typeswitch ($n)


[Gru08]



return

element

node-name($e)

$e( except $a)


else ()

for $c in $enode()


default return $n






Invoke xlate


foo

lty zoo=1gtbarltygt

ltxgt

foo

dArrdArrdArrdArr





foo

bar)

dArrdArrdArrdArr

ltx id=0 bar=gt

foo

lty zoo=1gtbarltygt

ltxgt



bull (namespaces)


bull (namespaces)





1 Introduction

2 XML Basics

3 Schema definition






97 Overview

uumluumluumluuml

uumluumluumluuml

uumluuml


to XML

6 SQLXML

7 XML processing


11 XML storage II


13 Systems


uumluumluumluuml

uumluuml




97 References

ndash M Scholl








97 References





bull Now or

bull Room IZ 232




or on appointment






let $x = ltxgt

let $y = ltygt







Solution


ndash A join query




ltagt





ltxgt

for $c in $abc



Result





ltagt





ltxgt

for $c in $abc

return ltgroupgt



ltgroupgt








larr empty group













return ltgroupgt




return ltgroupgt

ltcgt $c ltcgt


ltgroupgt

91 Introduction

92 Preliminaries


9 XQuery

94 FLWOR Semantics























[Gru08]


return fnname($a) )


return $adpath()





Reverse a sequence





[Gru08]



return $i





[Gru08]





Questions











[Gru08]


localhmm(ltagtltbgt


ltagt)





$from as xsstring

$to as xsstring)

typeswitch ($n)


[Gru08]



return

element

node-name($e)

$e( except $a)


else ()

for $c in $enode()


default return $n






Invoke xlate


foo

lty zoo=1gtbarltygt

ltxgt

foo

dArrdArrdArrdArr





foo

bar)

dArrdArrdArrdArr

ltx id=0 bar=gt

foo

lty zoo=1gtbarltygt

ltxgt



bull (namespaces)


bull (namespaces)





1 Introduction

2 XML Basics

3 Schema definition






97 Overview

uumluumluumluuml

uumluumluumluuml

uumluuml


to XML

6 SQLXML

7 XML processing


11 XML storage II


13 Systems


uumluumluumluuml

uumluuml




97 References

ndash M Scholl








97 References





bull Now or

bull Room IZ 232




or on appointment




ndash A join query




ltagt





ltxgt

for $c in $abc



Result





ltagt





ltxgt

for $c in $abc

return ltgroupgt



ltgroupgt








larr empty group













return ltgroupgt




return ltgroupgt

ltcgt $c ltcgt


ltgroupgt

91 Introduction

92 Preliminaries


9 XQuery

94 FLWOR Semantics























[Gru08]


return fnname($a) )


return $adpath()





Reverse a sequence





[Gru08]



return $i





[Gru08]





Questions











[Gru08]


localhmm(ltagtltbgt


ltagt)





$from as xsstring

$to as xsstring)

typeswitch ($n)


[Gru08]



return

element

node-name($e)

$e( except $a)


else ()

for $c in $enode()


default return $n






Invoke xlate


foo

lty zoo=1gtbarltygt

ltxgt

foo

dArrdArrdArrdArr





foo

bar)

dArrdArrdArrdArr

ltx id=0 bar=gt

foo

lty zoo=1gtbarltygt

ltxgt



bull (namespaces)


bull (namespaces)





1 Introduction

2 XML Basics

3 Schema definition






97 Overview

uumluumluumluuml

uumluumluumluuml

uumluuml


to XML

6 SQLXML

7 XML processing


11 XML storage II


13 Systems


uumluumluumluuml

uumluuml




97 References

ndash M Scholl








97 References





bull Now or

bull Room IZ 232




or on appointment







ltagt





ltxgt

for $c in $abc

return ltgroupgt



ltgroupgt








larr empty group













return ltgroupgt




return ltgroupgt

ltcgt $c ltcgt


ltgroupgt

91 Introduction

92 Preliminaries


9 XQuery

94 FLWOR Semantics























[Gru08]


return fnname($a) )


return $adpath()





Reverse a sequence





[Gru08]



return $i





[Gru08]





Questions











[Gru08]


localhmm(ltagtltbgt


ltagt)





$from as xsstring

$to as xsstring)

typeswitch ($n)


[Gru08]



return

element

node-name($e)

$e( except $a)


else ()

for $c in $enode()


default return $n






Invoke xlate


foo

lty zoo=1gtbarltygt

ltxgt

foo

dArrdArrdArrdArr





foo

bar)

dArrdArrdArrdArr

ltx id=0 bar=gt

foo

lty zoo=1gtbarltygt

ltxgt



bull (namespaces)


bull (namespaces)





1 Introduction

2 XML Basics

3 Schema definition






97 Overview

uumluumluumluuml

uumluumluumluuml

uumluuml


to XML

6 SQLXML

7 XML processing


11 XML storage II


13 Systems


uumluumluumluuml

uumluuml




97 References

ndash M Scholl








97 References





bull Now or

bull Room IZ 232




or on appointment










larr empty group













return ltgroupgt




return ltgroupgt

ltcgt $c ltcgt


ltgroupgt

91 Introduction

92 Preliminaries


9 XQuery

94 FLWOR Semantics























[Gru08]


return fnname($a) )


return $adpath()





Reverse a sequence





[Gru08]



return $i





[Gru08]





Questions











[Gru08]


localhmm(ltagtltbgt


ltagt)





$from as xsstring

$to as xsstring)

typeswitch ($n)


[Gru08]



return

element

node-name($e)

$e( except $a)


else ()

for $c in $enode()


default return $n






Invoke xlate


foo

lty zoo=1gtbarltygt

ltxgt

foo

dArrdArrdArrdArr





foo

bar)

dArrdArrdArrdArr

ltx id=0 bar=gt

foo

lty zoo=1gtbarltygt

ltxgt



bull (namespaces)


bull (namespaces)





1 Introduction

2 XML Basics

3 Schema definition






97 Overview

uumluumluumluuml

uumluumluumluuml

uumluuml


to XML

6 SQLXML

7 XML processing


11 XML storage II


13 Systems


uumluumluumluuml

uumluuml




97 References

ndash M Scholl








97 References





bull Now or

bull Room IZ 232




or on appointment









return ltgroupgt




return ltgroupgt

ltcgt $c ltcgt


ltgroupgt

91 Introduction

92 Preliminaries


9 XQuery

94 FLWOR Semantics























[Gru08]


return fnname($a) )


return $adpath()





Reverse a sequence





[Gru08]



return $i





[Gru08]





Questions











[Gru08]


localhmm(ltagtltbgt


ltagt)





$from as xsstring

$to as xsstring)

typeswitch ($n)


[Gru08]



return

element

node-name($e)

$e( except $a)


else ()

for $c in $enode()


default return $n






Invoke xlate


foo

lty zoo=1gtbarltygt

ltxgt

foo

dArrdArrdArrdArr





foo

bar)

dArrdArrdArrdArr

ltx id=0 bar=gt

foo

lty zoo=1gtbarltygt

ltxgt



bull (namespaces)


bull (namespaces)





1 Introduction

2 XML Basics

3 Schema definition






97 Overview

uumluumluumluuml

uumluumluumluuml

uumluuml


to XML

6 SQLXML

7 XML processing


11 XML storage II


13 Systems


uumluumluumluuml

uumluuml




97 References

ndash M Scholl








97 References





bull Now or

bull Room IZ 232




or on appointment



91 Introduction

92 Preliminaries


9 XQuery

94 FLWOR Semantics























[Gru08]


return fnname($a) )


return $adpath()





Reverse a sequence





[Gru08]



return $i





[Gru08]





Questions











[Gru08]


localhmm(ltagtltbgt


ltagt)





$from as xsstring

$to as xsstring)

typeswitch ($n)


[Gru08]



return

element

node-name($e)

$e( except $a)


else ()

for $c in $enode()


default return $n






Invoke xlate


foo

lty zoo=1gtbarltygt

ltxgt

foo

dArrdArrdArrdArr





foo

bar)

dArrdArrdArrdArr

ltx id=0 bar=gt

foo

lty zoo=1gtbarltygt

ltxgt



bull (namespaces)


bull (namespaces)





1 Introduction

2 XML Basics

3 Schema definition






97 Overview

uumluumluumluuml

uumluumluumluuml

uumluuml


to XML

6 SQLXML

7 XML processing


11 XML storage II


13 Systems


uumluumluumluuml

uumluuml




97 References

ndash M Scholl








97 References





bull Now or

bull Room IZ 232




or on appointment





















[Gru08]


return fnname($a) )


return $adpath()





Reverse a sequence





[Gru08]



return $i





[Gru08]





Questions











[Gru08]


localhmm(ltagtltbgt


ltagt)





$from as xsstring

$to as xsstring)

typeswitch ($n)


[Gru08]



return

element

node-name($e)

$e( except $a)


else ()

for $c in $enode()


default return $n






Invoke xlate


foo

lty zoo=1gtbarltygt

ltxgt

foo

dArrdArrdArrdArr





foo

bar)

dArrdArrdArrdArr

ltx id=0 bar=gt

foo

lty zoo=1gtbarltygt

ltxgt



bull (namespaces)


bull (namespaces)





1 Introduction

2 XML Basics

3 Schema definition






97 Overview

uumluumluumluuml

uumluumluumluuml

uumluuml


to XML

6 SQLXML

7 XML processing


11 XML storage II


13 Systems


uumluumluumluuml

uumluuml




97 References

ndash M Scholl








97 References





bull Now or

bull Room IZ 232




or on appointment





Reverse a sequence





[Gru08]



return $i





[Gru08]





Questions











[Gru08]


localhmm(ltagtltbgt


ltagt)





$from as xsstring

$to as xsstring)

typeswitch ($n)


[Gru08]



return

element

node-name($e)

$e( except $a)


else ()

for $c in $enode()


default return $n






Invoke xlate


foo

lty zoo=1gtbarltygt

ltxgt

foo

dArrdArrdArrdArr





foo

bar)

dArrdArrdArrdArr

ltx id=0 bar=gt

foo

lty zoo=1gtbarltygt

ltxgt



bull (namespaces)


bull (namespaces)





1 Introduction

2 XML Basics

3 Schema definition






97 Overview

uumluumluumluuml

uumluumluumluuml

uumluuml


to XML

6 SQLXML

7 XML processing


11 XML storage II


13 Systems


uumluumluumluuml

uumluuml




97 References

ndash M Scholl








97 References





bull Now or

bull Room IZ 232




or on appointment





[Gru08]





Questions











[Gru08]


localhmm(ltagtltbgt


ltagt)





$from as xsstring

$to as xsstring)

typeswitch ($n)


[Gru08]



return

element

node-name($e)

$e( except $a)


else ()

for $c in $enode()


default return $n






Invoke xlate


foo

lty zoo=1gtbarltygt

ltxgt

foo

dArrdArrdArrdArr





foo

bar)

dArrdArrdArrdArr

ltx id=0 bar=gt

foo

lty zoo=1gtbarltygt

ltxgt



bull (namespaces)


bull (namespaces)





1 Introduction

2 XML Basics

3 Schema definition






97 Overview

uumluumluumluuml

uumluumluumluuml

uumluuml


to XML

6 SQLXML

7 XML processing


11 XML storage II


13 Systems


uumluumluumluuml

uumluuml




97 References

ndash M Scholl








97 References





bull Now or

bull Room IZ 232




or on appointment











[Gru08]


localhmm(ltagtltbgt


ltagt)





$from as xsstring

$to as xsstring)

typeswitch ($n)


[Gru08]



return

element

node-name($e)

$e( except $a)


else ()

for $c in $enode()


default return $n






Invoke xlate


foo

lty zoo=1gtbarltygt

ltxgt

foo

dArrdArrdArrdArr





foo

bar)

dArrdArrdArrdArr

ltx id=0 bar=gt

foo

lty zoo=1gtbarltygt

ltxgt



bull (namespaces)


bull (namespaces)





1 Introduction

2 XML Basics

3 Schema definition






97 Overview

uumluumluumluuml

uumluumluumluuml

uumluuml


to XML

6 SQLXML

7 XML processing


11 XML storage II


13 Systems


uumluumluumluuml

uumluuml




97 References

ndash M Scholl








97 References





bull Now or

bull Room IZ 232




or on appointment






$from as xsstring

$to as xsstring)

typeswitch ($n)


[Gru08]



return

element

node-name($e)

$e( except $a)


else ()

for $c in $enode()


default return $n






Invoke xlate


foo

lty zoo=1gtbarltygt

ltxgt

foo

dArrdArrdArrdArr





foo

bar)

dArrdArrdArrdArr

ltx id=0 bar=gt

foo

lty zoo=1gtbarltygt

ltxgt



bull (namespaces)


bull (namespaces)





1 Introduction

2 XML Basics

3 Schema definition






97 Overview

uumluumluumluuml

uumluumluumluuml

uumluuml


to XML

6 SQLXML

7 XML processing


11 XML storage II


13 Systems


uumluumluumluuml

uumluuml




97 References

ndash M Scholl








97 References





bull Now or

bull Room IZ 232




or on appointment







Invoke xlate


foo

lty zoo=1gtbarltygt

ltxgt

foo

dArrdArrdArrdArr





foo

bar)

dArrdArrdArrdArr

ltx id=0 bar=gt

foo

lty zoo=1gtbarltygt

ltxgt



bull (namespaces)


bull (namespaces)





1 Introduction

2 XML Basics

3 Schema definition






97 Overview

uumluumluumluuml

uumluumluumluuml

uumluuml


to XML

6 SQLXML

7 XML processing


11 XML storage II


13 Systems


uumluumluumluuml

uumluuml




97 References

ndash M Scholl








97 References





bull Now or

bull Room IZ 232




or on appointment





bull (namespaces)


bull (namespaces)





1 Introduction

2 XML Basics

3 Schema definition






97 Overview

uumluumluumluuml

uumluumluumluuml

uumluuml


to XML

6 SQLXML

7 XML processing


11 XML storage II


13 Systems


uumluumluumluuml

uumluuml




97 References

ndash M Scholl








97 References





bull Now or

bull Room IZ 232




or on appointment



1 Introduction

2 XML Basics

3 Schema definition






97 Overview

uumluumluumluuml

uumluumluumluuml

uumluuml


to XML

6 SQLXML

7 XML processing


11 XML storage II


13 Systems


uumluumluumluuml

uumluuml




97 References

ndash M Scholl








97 References





bull Now or

bull Room IZ 232




or on appointment






97 References

ndash M Scholl








97 References





bull Now or

bull Room IZ 232




or on appointment






97 References





bull Now or

bull Room IZ 232




or on appointment



bull Now or

bull Room IZ 232




or on appointment



9. xml query languages iii â€“ xquery

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