Re: BUG #15071: Error in PostgreSQL-specific :: type cast

On Fri, Feb 16, 2018 at 12:57 PM, PG Bug reporting form
<noreply(at)postgresql(dot)org> wrote:

...
> SELECT -32768::smallint
> ^ERROR: smallint out of range

This is interpreted as -(32768::smallint)

...
> Standard-syntax type casts are workes correctly:
> SELECT cast(-32768 as smallint)

This is not.

When in doubt, put parenthesis

postgres=# select (-32768)::smallint;
int2
--------
-32768
(1 row)

postgres=# select -(32768::smallint);
ERROR: smallint out of range
postgres=# select -32768::smallint;
ERROR: smallint out of range

And IIRC, expression with implicit casts ( like when comparing
constnat to columns) work because they use the conversion from
text/unknown...

postgres=# select '-32768'::smallint;
int2
--------
-32768
(1 row)

Francisco Olarte.