A quantified predicate compares a value with a set of values produced by a subselect.
expression comparison-operator SOME | ANY | ALL ( subselect )
The expression must not evaluate to a reference type.
When SOME or ANY is specified the result of the predicate is as follows:
TRUE if the comparison is true for at least one value returned by the subselect.
FALSE if the subselect is empty or if the comparison is false for every value returned by the subselect.
UNKNOWN if the comparison is not true for all of the values returned by the subselect and at least one of the comparisons is unknown because of a null value.
When ALL is specified the result of the predicate is as follows:
TRUE if the subselect returns empty or if the comparison is true to every value returned by the subselect.
FALSE if the comparison is false for at least one value returned by the subselect.
UNKNOWN if the comparison is not false for all values returned by the subselect and at least one comparison is unknown because of a null value.