Patryk Kordylewski <pk(at)fooby(dot)de> writes:
> i've found a strange behaviour when you have overloaded functions with
> the same name and different argument types and try to call them with NULL.
> The stored procedures with "text" and "text[]" argument type gets called
> - the variants with "integer" / "integer[]" produce the, i think
> expected, behaviour and raise an exception "ERROR: FUNCTION
> foo(unknown) IS NOT UNIQUE".
Yeah, this is expected. There's a weak preference to resolve NULL as
text if there's no other way to determine its type. (It's handled the
same as an undecorated string literal.)
regards, tom lane