Re: Check for an empty result

Hi Craig!

--- On Fri, 2/13/09, Craig Ringer <craig@postnewspapers.com.au> wrote:

> Eus wrote:
> > Hi Ho!
> >
> > Is there a way to check whether or not a subquery
> returns an empty result set?
>
> "EXISTS"
>
> SELECT blah FROM blah WHERE EXISTS (SELECT 1 FROM tablename
> WHERE ...);

Thank you. Previously I tried: "... WHERE (...) IS NULL;". Of course, it didn't work.

> > postgre check "empty result set"
>
> It's not "postgre". It's PostgreSQL, or
> "postgres". This matters when
> you're searching.

Oh, okay. Thanks for telling me.

> --
> Craig Ringer

Best regards,
Eus (FSF member #4445)

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