Evaluate the following SQL statement:
Which statement is true regarding the above query if one of the values generated by the
subquery is null?
A.
It produces an error.
B.
It executes but returns no rows.
C.
It generates output for null as well as the other values produced by the subquery.
D.
It ignores the null value and generates output for the other values produced by the
subquery.
D
D
D
When we use IN, we’re telling SQL to take a value and compare it against every value or set of values in a list using = operator.
If any NULL values exist, as what the question mentioned “… one of the values generated by the subquery is null”, a row will not be returned even if both values are NULL.
In sum, the IN clause compares values returned by the subquery and filters out rows in the outer query.