RE: Should we still be using select/omit in logical files?

The mere existence of a select omit logical file will cause the SQL request to go CQE _unless_ the IGNORE_DERIVED_INDEX option in the QAQQINI file is set to *YES. If you are using SQL to do the I/O select/omits are definitely not the way to go.

~Zach
-----Original Message-----
From: midrange-l-bounces@xxxxxxxxxxxx [mailto:midrange-l-bounces@xxxxxxxxxxxx] On Behalf Of David FOXWELL
Sent: Tuesday, June 16, 2009 6:01 AM
To: Midrange Systems Technical Discussion
Subject: Should we still be using select/omit in logical files?

Hi all,

There doesn't seem to be any sharing of access paths when select/omit is used in a LF.

I have :

PF1 with currently a little over 1 million client records.
7 LF on this PF. LF1 to LF7

Client records that are no longer active get flagged in the PF.

To avoid having to constantly check each record to see if it was active, SELECT has been used in each of the logicals.

The problem : it would seem that it is not possible to share access paths. I'm creating an LF8 with key K1

In LF2, I have K1, K2, K3, K4, K5, K6
In LF4, I have K1, K3

I created LF8 following the advice from SYSIXADV. The performance on the SQL request in question is greatly enhanced. However, if I understand correctly, SQE would not use LF8 if I used SELECT as in the other LF.

Should we still be using select/omit in logical files?

Thanks.