Karpova_bazy_dannyh

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(n+12)*R 100

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12*(R l.A)-n*(R2.B) ' m

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R1.A (m+n*(R2 )/12

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R1 NATURAL JOIN R2

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R3 = R1ER1-A]

R4 = R2CR2.B]

R5 = R3*[ ]*R4

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291

SELECT R1.A

FROM R1 WHERE R1.B IN

(SELECT R2 FROM R2 WHERE R1.C = R2.D)

(SELECT R1.A

FROM RL R2

WHERE R 1 . A = R2 AND R1.C = R2.D)

:

(SELECT R1.A FROM R1 WHERE R1.X

(SELECT AVG (R2 FROM R2 WEHRE R1.C = R2.0)

(SELECT R1.A FROM R1. R3

WHERE R1.C = R3 D AND 1l.K - R3.L5 R3 = SELECT R2.0, L AVG (R2 6)

FROM R2 GROUP BY R2 0

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