It's because the query parser can't decide at the point of planning whether
you are about to supply a:
LIKE %GALA% or a GALA%. The first can't use an index and the second can.

Cheers,

JAC.


""csswa"" <csswa@...> wrote in message
news:ag9t5u+cdn4@......

>
> The implication here is that the overhead of parameterizing makes the
> procedure run 15+ times slower. I dunno -- maybe it's reasonable to
> assume 15 extra instructions/clock ticks are required to manipulate
> the :param instead of a simple constant like 'GLAX%'.
>
> Out of curiosity, Ben, try is with STARTING WITH in place of LIKE.
> Sorry, I don't have an explanation for you, but some experimenting
> may yield more clues.
>
> Regards,
> Andrew Ferguson
> -- I never said I had no idea about most of the things you said I
> said I had no idea about.
>
>
> --- In ib-support@y..., "Ben Johnson" <ben_johns@r...> wrote:
> > Hi,
> >
> > Yes, if I use LIKE :sString it is taking 00:00:00:0930
> > seconds
> >
> > But if I hardcode it like LIKE 'GLAX%' it takes only
> > 00:00:00:0050 seconds!
> > Ben
> >
> >
> > On Sun, 07 Jul 2002 Thomas Steinmaurer wrote :
> > >Ben,
> > >
> > > > Thanks for your reply.
> > > >
> > > > I am using only 'GLAX%', sString can be 'G%' or 'GL%' or
> > > > 'GLA%', the plan tab in IBConsole shows it is using index.
> > >
> > >So the query should be fast enough. Is there any other problem
> > >with the LIKE clause?
> > >
> > >
> > >Regards,
> > >Thomas Steinmaurer
> > >IB LogManager 2.0 - The Logging/Auditing Tool for InterBase and
> > >Firebird
> > >http://www.iblogmanager.com
> > >
> > >
> > >------------------------ Yahoo! Groups Sponsor
> > >
> > >To unsubscribe from this group, send an email to:
> > >ib-support-unsubscribe@e...
> > >
> > >
> > >
> > >Your use of Yahoo! Groups is subject to
> > >http://docs.yahoo.com/info/terms/
> > >
> > >
> >
> > _________________________________________________________
> > There is always a better job for you at Monsterindia.com.
> > Go now http://monsterindia.rediff.com/jobs
>
>
>
> To unsubscribe from this group, send an email to:
> ib-support-unsubscribe@egroups.com
>
>
>
> Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
>
>
>