Re: SQL to only check for existence:

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

Vernon,

Your result would have been instant because you didn't specify a where clause.

do you think set :$itemfound (select 1...
  will be faster than

  select '1' into :$itemfound.....

?

thanks,

Rick

On 4/18/06, vhamberg@xxxxxxxxxxx <vhamberg@xxxxxxxxxxx> wrote:
> Try pasting the following into an SQLRPGLE source and substitute your library 
> and file for qiws/qcustcdt. I ran it over a file with c.350,000 records, it 
> was instant.
>
> di                s              1p 0
> c/exec sql
> c+ set :i = (select 1 from sysibm/sysdummy1
> c+           where exists(select * from qiws/qcustcdt))
> c/end-exec
> c                   eval      *inlr = *on
>
> -------------- Original message --------------
> From: "rick baird" <rick.baird@xxxxxxxxx>
>
> > 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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