Consider the statement

SELECT $*$ FROM A JOIN B ON A$.x=$ B$.x$ WHERE A$.z=500$

Assume that the probability of the join condition being satisfied is $p,$ the probability of the

where clause being satisfied is $q,$ and the number of records in tables A and $B$ are $N_A$ and

$N_B,$ respectively

$($a$)$ What is the communication complexity of the statement if the join operation is done

first followed by a select

$($b$)$ What is the communication complexity of the statement if the select operation is

done first followed by a join