oracle select query
Post on 16-Apr-2017
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SELECT OPERATION
IN Oracle
Developer : Nihar R Paital
Select query retrieves information from a database and structures them into a result table.• Writing SELECT queries is a skill that you need a lot in your job.• Basically SELECT queries are difficult when there is the question of the occurrences of the following.
Using Aggregate FunctionsWithout GROUP BYWith GROUP BY
JOINSub Query
These Structures can be easily understood if you will follow the diagrammatic representation given below.
What you will get from the Diagram?
This digram gives a brief idea about How to write a query.It contains all most all keywords and clauses, which are used in SQL query, and those which are
supported in OracleYou can also collect a huge collection of syntaxes for SELECT query.
Developer : Nihar R Paital
WHERE
GROUP BY
ORDER BY
INNER JOIN
<AGG(f1)...>* <[f1], ... ><[f1], AGG(f2)>
SELECT
< [t1.][f1]...>< [t1.][f1],... AGG([t2.][f2])...>
FROM <t1>FROM <t1>, <t2>,...
<PREDICATE>
<PREDICATE on Aggregate>
DISTINCT
HAVING
ON
FROM
<table_name>...
<table_name>...
LEFT/RIGHT OUTER JOIN
<[t1.][f1]...>
JOINPREDICATE
<[t1.][f1]...>
Cross join Self
join
Developer : Nihar R Paital
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