Question: Consider two tables X ( A , B ) and Y ( A , C ) . A , B , C are attributes. A

Consider two tables X(A,B) and Y(A,C). A, B, C are attributes. A is the primary key in both X and Y. Assume that NULL values are NOT permitted for A, B, and C; and the two tables X, Y are not empty.
Decide if the following two queries are equivalent (that is, if they are guaranteed to produce the same answer no matter what the actual data in X and Y are. Do not consider the sequence of the returned rows).
1: select A from Y where A in (select A from X);
2: select A from X where A in (select A from Y);
Group of answer choices
True
False

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