Re: SQL to only check for existence

["rick baird" <rick.baird@xxxxxxxxx>]

Mark,

the only thing I don't have (yet) is the fetch first 1.

I'll give it a whirl.

thanks!

Rick

On 4/18/06, Mark Adkins <adkinsm@xxxxxxxxxx> wrote:
> Hey Rick,
>
> This is the optimum solution I believe.
>
> FOUND = *OFF
> SELECT '1' INTO :FOUND
> FROM FILE
> WHERE FIELD LIKE '___abc___'
> FETCH FIRST 1 ROWS ONLY
>
> Mark
>
> > ----- Message from "rick baird" <rick.baird@xxxxxxxxx> on Tue, 18
> > Apr 2006 10:56:16 -0400 -----
> >
> > To:
> >
> > "Midrange Systems Technical Discussion" <midrange-l@xxxxxxxxxxxx>,
> > "RPG programming on the AS400 / iSeries" <rpg400-l@xxxxxxxxxxxx>
> >
> > Subject:
> >
> > SQL to only check for existence:
> >
> > hey all,
> >
> > Is there a way to run an SQL statement that doesn't (necessarily)
> > return anything, but only checks for the existence of one or more
> > records based on a where statement - similar to a SETLL and %found?
> >
> > I've got a rather complicated SQL statement using:
> > LIKE '___abc___'    or it could be:
> > LIKE ______xyz'
> >
> > - over a very large file, and I'm having performance issues.
> >
> > I don't want to do a count(), because I don't care how many, only that
> > at least one exists.   with count, it would have to read through the
> > entire file to determine it.
> >
> > I also tried just doing a select - optimize for 1 row and a single
> > fetch, but that seemed to take forever too.  It appears as if it is
> > searching the entire file, instead of stopping at the first one.
> >
> > help!
> >
> > Rick
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