At 09:27 PM 15/06/2006, you wrote:

> >
> > and((:WHS='')or(WHS=:WHS))
>
>Why? - it works perfectly well in stored procedure code

In stored procedure code, it *is* a variable. Don't be confused by
the conventions. In Delphi, the :PARAM is the naming convention for
replaceable parameters. In PSQL, it is the convention for signalling
that you are referring to a variable.

THEY ARE DIFFERENT USES OF THE SAME CONVENTION. AFAIR, there is an
FAQ explaining this difference.

>
> > If it means this:
> >
> > and (WHS = '' OR WHS = :WHS)
> >
> > then write it that way.
> >
>
>No - it doesn't mean that. It means if the user doesn't fill in the WHS box
>it doesn't filter.
>
> > If you want your empty string constant to represent null in
> > the database, then write it this way:
> >
> > amd (WHS is null or WHS = :WHS)
> >
>I'm not interested in null, only an empty string or a character.

Then (WHS ='' or WHS = :WHS)

Helen