Showthat the semi-join operation is not commutative, that is, T1 semi-joined with T2 is not the same as T2 semi-joined with T1.
What will be an ideal response?
The semi-join is the projection over the columns of T1 of the join of T1 and T2:
?attributes(T1) (T1 join-condition T2)
The projection over the attributes of T1 is different than the projection over the
attributes of T2, unless T1 and T2 happen to share exactly the same attribute set.
Computer Science & Information Technology
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Indicate whether the statement is true or false
Computer Science & Information Technology
What will be the outcome of the following query? SELECT replace(9999.00-1,'8',88) FROM dual;
A. 99988 B. 9998 C. 9999.88 D. 999
Computer Science & Information Technology