"Glen Parker" <glenebob@nwlink.com> writes:
> ERROR: Unable to identify an operator '=' for types 'character' and
> 'character varying'
The reason it's unhappy is that it has no reasonable way to make a
choice between using char and varchar comparison (which are not the
same; the former is insensitive to trailing blanks). You need a
cast to tell it what to do.
regards, tom lane