Karpova_bazy_dannyh

101

(SELECT Rl FROM Rl

WHERE Rl <= 2 OR Rl IS NULL)

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FR0M R3

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UPDATE R5

SET R5 = 50%

WHERE R5 IN (SELECT Rl

FROM Rl R2

WHERE Rl = R2 AND Rl = 5

GROOP BY Rl

HAVING COUNT(*) = (SELECT COUNT(*)

FROM R3

WHERE R2 = R3

GROOP BY R3 ))

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