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in Databases 164 views
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R is not the primary key in relation r2 therefore redundant data will result maximum selection of tuples.
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b is correct answer.

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Given R1(P, Q, R) and R2(R ,U, V) where R is primary key in R1 and U is primary key in R2.
R in R1 is primary key so it should contain unique values assume 1,2,3,......1500(1500tuples)
There is no constraint on R in R2 so it can contain duplicate values assume 1,1,1,...1(2000 tuples)
Natural join is performed on the Common attribute i.e R
1 in R( R1 table) can map with 2000 1's in R( R2 table).
Hence maximum 2000 tuples are possible in natural join

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when 1500 wud be the answer then???

plz check this too. . .https://gateoverflow.in/3553/gate2006-it-14

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Now I got it clearly....  Thank u so much

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