Re: CONCAT function

Vinayak <vinpokale@gmail.com> writes:
> The pg_catalog.concat() is defined as STABLE function.
> why was STABLE preferred for concat() over IMMUTABLE?

concat() invokes datatype output functions, which are not necessarily
immutable.  An easy example is that timestamptz_out's results depend
on the TimeZone setting.

            regards, tom lane