Re: Database Access Path Question

[Paul Tuohy <tuohyp@xxxxxxxxxxxxx>]

Nelson,

If the two logicals have the same keys and select field, but select on 
different data in that select field they will NOT use the same access 
path. The access paths will only contain the keys of the records that 
satisfy the selection criteria.

If you specify DYNSLT, then the selection criteria is ignored (in 
regards to the access paths), so the access path will be shared between 
the two logicals (since the key definition is identical. You will take 
the selection "hit" at run time, when you use the access path.

HTH

Paul Tuohy

Smith, Nelson wrote:
> The DYNSLT discussion is interesting, but doesn't directly address my
> original question:
>
> If two logicals have the same keys and select field, but select on different
> data in that select field, will they use the same access path, part of the
> access path, or not at all? 
>
> > -----Original Message-----
> > From:	Steve Richter [SMTP:srichter@autocoder.com]
> > Sent:	Thursday, February 06, 2003 10:35 AM
> > To:	Midrange Systems Technical Discussion
> > Subject:	RE: Database Access Path Question
> >
> > It depends on how many records meet the selection criteria. One factor
> > that
> > will always favor dynslt is that data mgmt can select records much faster
> > than rpg code can.
> >
> > accpth(*rebld or *dly) is another option.  Create standalone logicals w/o
> > dynslt.  If they are used once a week in batch or if conditions permit in
> > an
> > online appl, tell the system to *DLY accpth maint or *REBLD the accpth
> > with
> > the file is opened.
> >
> > Steve
> >
> > -----Original Message-----
> > From: midrange-l-bounces@midrange.com
> > [mailto:midrange-l-bounces@midrange.com]On Behalf Of David Dunfield
> > Sent: Thursday, February 06, 2003 10:12 AM
> > To: Midrange Systems Technical Discussion
> > Subject: RE: Database Access Path Question
> >
> >
> > DYNSLT may be an option, but we have experienced less than great
> > results using dynslt in reading records. It does work, but it still
> > reads all records in access path to select only those DYNSLT.
> >
> >
> > _______________________________________________
> > This is the Midrange Systems Technical Discussion (MIDRANGE-L) mailing
> > list
> > To post a message email: MIDRANGE-L@midrange.com
> > To subscribe, unsubscribe, or change list options,
> > visit: http://lists.midrange.com/mailman/listinfo/midrange-l
> > or email: MIDRANGE-L-request@midrange.com
> > Before posting, please take a moment to review the archives
> > at http://archive.midrange.com/midrange-l.
>
>
> ************************************************************************************************************************************************************************************************************
> This message originates from Lincare Holdings Inc. It contains information which may be confidential or privileged and is intended only for the individual or entity named above.
> It is prohibited for anyone else to disclose, copy, distribute or use the contents of this message. 
> All personal messages express views solely of the sender, which are not to be attributed to Lincare Holdings Inc., and may not be copied or distributed without this disclaimer. 
> If you received this message in error, please notify us immediately at MailAdmin@lincare.com or (800) 284-2006.
> ************************************************************************************************************************************************************************************************************
>
> _______________________________________________
> This is the Midrange Systems Technical Discussion (MIDRANGE-L) mailing list
> To post a message email: MIDRANGE-L@midrange.com
> To subscribe, unsubscribe, or change list options,
> visit: http://lists.midrange.com/mailman/listinfo/midrange-l
> or email: MIDRANGE-L-request@midrange.com
> Before posting, please take a moment to review the archives
> at http://archive.midrange.com/midrange-l.