To determine if a value exists in a subquery or scalar value list you can use
in operator like:
> select 1 in (1, 2) true
all go a step further by allowing for an operator in the special
construct which is used against each value in the subquery or array (no scalar
value list for these constructs).
> select 1 = any(Array[1, 2, 3]) true > select 1 > any(Array[1, 2, 3]) false
> select 17 <> any(Array[2, 4, 8]) true > select 17 < any(Array[2, 4, 8]) false
some is a synonym for any.