Re: Indexes vs Logical Files

[Charles Wilt <charles.wilt@xxxxxxxxx>]

I'm 100% sure you are mis-remembering...

Charles

On Fri, Oct 13, 2023 at 8:19 AM Gavin Inman <midrangelist@xxxxxxxxxxxxxx>
wrote:

> IBM DB2 Engineer Mark Anderson was the one who told me this.  If a
> physical has keys, it is forced to COE.
>
> On 10/13/2023 9:33 AM, Charles Wilt wrote:
>
> That has never been the case.
>
> And now-a-days, pretty much everything goes through the SQE.
>
> Originally, if you referenced a LF on an SQL statement, you forced the use
> of the CQE.
>
> Perhaps that's what you're thinking of.  But again, even that is no longer
> the case.
>
>
> Charles
>
> On Fri, Oct 13, 2023 at 6:52 AM Gavin Inman<midrangelist@xxxxxxxxxxxxxx>
> wrote:
>
> > Years ago it was explained to me that if the physical has keys, it's
> > forced to use the older database engine.  Unless something has changed,
> > I believe that's still true today.
> >
> > Gavin.
> >
> > On 10/13/2023 8:47 AM, Greg Wilburn wrote:
> >
> > I've been using Index Advisor and Run Sql Scripts "Run and Explain" to
> > analyze some of our queries.  I'm looking for increased performance.
> >
> > I have a large file/table OEBOXCBX with a logical files defined with the
> > following keys:
> >
> > LF #1: BXCOM#, BXORD#, BXREL#, BXBOX#, BXPRT#
> > LF #2: BXCOM#, BXORD#, BXREL#, BXBXNO, BXPRT#
> >
> > I ran an SQL statement over a complex SQL view that contains this file.
> > RSS Run and Explain recommended the following index:
> > CREATE INDEX ASTHHOBJ/OEBOXCBX_IDX
> >       ON ASTHHOBJ/OEBOXCBX (BXCOM# ASC, BXORD# ASC, BXREL# ASC) UNIT ANY
> > KEEP IN MEMORY NO;
> >
> > My question is why the SQE wouldn't use one of the existing logical files
> > as an index?  As an RPG guy, this makes no sense to me.
> >
> > TIA,
> > Greg
> >
> > [Logo]<https://www.totalbizfulfillment.com/>      Greg Wilburn
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> >
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