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Given two union compatible relations $R_1(A, B)$ and $R_2 (C, D)$, what is the result of the operation $R_1 \Join_{ A = C \wedge B = D} R_2$?

  1. $R_1 \cup R_2$

  2. $R_1 \times R_2$

  3. $R_1 – R_2$

  4. $R_1 \cap R_2$

asked in Databases by Veteran (59.5k points)
edited by | 1.1k views
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Please explain

1 Answer

+22 votes
Best answer

This question is an example of Theta Join,

 

The join here will be selecting only those tuples where A = C and B = D, meaning it is the intersection. D option.

answered by Veteran (355k points)
edited


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