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Page 1: SELECT DISTINCT price - Stanford Universityi.stanford.edu/~ullman/fcdb/aut02/sql2.pdf · S T SELECT DISTINCT price FROM Sells; U V (SELECT drinker FROM Frequents) EXCEPT ALL (SELECT

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Page 2: SELECT DISTINCT price - Stanford Universityi.stanford.edu/~ullman/fcdb/aut02/sql2.pdf · S T SELECT DISTINCT price FROM Sells; U V (SELECT drinker FROM Frequents) EXCEPT ALL (SELECT

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SELECT DISTINCT price

FROM Sells;

U

V

(SELECT drinker FROM Frequents)

EXCEPT ALL

(SELECT drinker FROM Likes);V

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Likes NATURAL JOIN Serves;V

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Drinkers JOIN Frequents ON

name = drinker;

Page 3: SELECT DISTINCT price - Stanford Universityi.stanford.edu/~ullman/fcdb/aut02/sql2.pdf · S T SELECT DISTINCT price FROM Sells; U V (SELECT drinker FROM Frequents) EXCEPT ALL (SELECT

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SELECT AVG(price)

FROM Sells

WHERE beer = ’Bud’;

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SELECT COUNT(DISTINCT price)

FROM Sells

WHERE beer = ’Bud’;

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Page 4: SELECT DISTINCT price - Stanford Universityi.stanford.edu/~ullman/fcdb/aut02/sql2.pdf · S T SELECT DISTINCT price FROM Sells; U V (SELECT drinker FROM Frequents) EXCEPT ALL (SELECT

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SELECT beer, AVG(price)

FROM Sells

GROUP BY beer;

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Page 5: SELECT DISTINCT price - Stanford Universityi.stanford.edu/~ullman/fcdb/aut02/sql2.pdf · S T SELECT DISTINCT price FROM Sells; U V (SELECT drinker FROM Frequents) EXCEPT ALL (SELECT

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INSERT INTO Likes

VALUES(’Sally’, ’Bud’);

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Page 6: SELECT DISTINCT price - Stanford Universityi.stanford.edu/~ullman/fcdb/aut02/sql2.pdf · S T SELECT DISTINCT price FROM Sells; U V (SELECT drinker FROM Frequents) EXCEPT ALL (SELECT

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INSERT INTO Likes(beer, drinker)

VALUES(’Bud’, ’Sally’);

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DELETE FROM Likes

WHERE drinker = ’Sally’ AND

beer = ’Bud’;

Page 7: SELECT DISTINCT price - Stanford Universityi.stanford.edu/~ullman/fcdb/aut02/sql2.pdf · S T SELECT DISTINCT price FROM Sells; U V (SELECT drinker FROM Frequents) EXCEPT ALL (SELECT

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DELETE FROM Likes;

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UPDATE Drinkers

SET phone = ’555 - 1212’

WHERE name = ’Fred’;

Page 8: SELECT DISTINCT price - Stanford Universityi.stanford.edu/~ullman/fcdb/aut02/sql2.pdf · S T SELECT DISTINCT price FROM Sells; U V (SELECT drinker FROM Frequents) EXCEPT ALL (SELECT

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UPDATE Sells

SET price = 4.00

WHERE price > 4.00;