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+2 votes
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asked in Databases by Loyal (2.7k points) | 37 views
R is not the primary key in relation r2 therefore redundant data will result maximum selection of tuples.
b is correct answer.

1 Answer

+1 vote
Best answer
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
answered by Boss (6.6k points)
selected by

when 1500 wud be the answer then???

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

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


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