"Josh Berkus" <josh@agliodbs.com> writes:
> 4. If I pass a NULL to any of the parameters of a PL/PGSQL
> function, any (other) VARCHAR parameters are set to NULL as
> well.
Not only varchar --- any other parameters, period. And not only that,
but the result is taken as NULL no matter what you try to return.
This is a longstanding deficiency that is fixed by the new function
manager in 7.1.
regards, tom lane