Re: Concat error in PL/pgsql

Hans Peter Wuermli <wurmli@freesurf.ch> writes:
> Within a plpgsql function, concatenating TEXT strings from tables that
> allow NULL values return nil results.

That's not a bug: NULL concatenated with anything produces NULL,
per SQL92 specification.

If you want a NULL to act like an empty string, try

    for r in select * from tconcattest loop
          output := output || coalesce(r.str, '''');

            regards, tom lane