"Pascal Rempenault" <prempenault(at)hubwoo(dot)com> writes:
> track=# select loginname, upper(loginname) from tperson where
> upper(loginname)='ADMIN';
> loginname | upper
> -----------+-------
> (0 rows)
I'm guessing that there are trailing blanks in loginname (possibly
because it's declared char(n) rather than varchar(n)). The result
of upper() is always of type text, so comparison to it treats the
trailing blanks as significant.
regards, tom lane