So, Ray, where do I find these rules? Are they written down somewhere
that I can get to and acquire a copy?
Jef.
- Partial Original Message-
No, it's true for all cases. UniVerse indexes are only used on
restrictions in the first WITH phrase in the query. That's one of the
rules.
In
nker" <[EMAIL PROTECTED]>
> To: u2-users@listserver.u2ug.org
> Subject: RE: [U2] Indexing & Optimization
> Date: Mon, 22 Oct 2007 08:02:37 -0500
>
>
> Isn't that true only when using 'AND' with the 'WITH' phrase? Using 'OR'
> w
Isn't that true only when using 'AND' with the 'WITH' phrase? Using 'OR'
would have to use the whole index/selection again.
-Original Message-
From: Ray Wurlod [mailto:[EMAIL PROTECTED]
Sent: Saturday, October 20, 2007 11:30 PM
To: u2-users@listserver.
One of the rules for UniVerse to use an index is that the restriction occurs in
the first WITH phrase. The reasoning is that the majority of records to be
excluded will have been excluded by the first WITH clause, and that therefore
the second WITH clause need only examine the record selected b
FYI...
This link has a nice summary of what the major RDBMS offer for the
EXPLAIN output:
http://www.aquafold.com/docs-ep-plan.html
It would be nice to have a version of Aquafold (or one of the many
similar multi-OS and multi-database 'aware' toolsets) available for
UniVerse too...ah, one day -
s UniVerse has two native query languages, but one database engine -
it's available for SQL and non-SQL queries.
-Original Message-
From: [EMAIL PROTECTED]
[mailto:[EMAIL PROTECTED] On Behalf Of john reid
Sent: Thursday, October 18, 2007 6:26 AM
To: u2-users@listserver.u2ug.
It appears that 'EXPLAIN' is somewhat documented via an internet
search, implying that it might be standard equipment for at least some
SQL's in order to show query plans. I did find a file on our system
named SQL.HELP. A search revealed 6 records containing 'EXPLAIN' but
it also contained a lot o
Could someone please explain the EXPLAIN results? The Help does not
show about EXPLAIN.
In particular, what does the index processing point out? I have 43,000
records that have A8="DRJ" but only a handful that will have A50="70" so
if I can get the SELECT to use A50 first that would be great. I c
