Correction! SQL can use Indexes with WHERE Conditions ... but the Syntax in
the Index WHERE Conditions and the SQL Statement WHERE conditions must be an
exact match.
The easiest way to avoid syntactical problems is , to create a view with all
columns and exactly the same WHERE conditions as in the CREATE INDEX
statement ... then access the data through this view.
... all other dependent (future) views then can be created on the top of the
view with the WHERE conditions.
Keep in mind: Contrary to SQL Indexes or DDS described logical files, a view
does not have a key (it is just a stored SELECT Statement), so there will be
no performance decrease when inserting or updating rows in the base table.
In this way you can really have thousands of views on the same table without
performance decrease ... the hardest thing would be to (re)find the
appropriate view.
Mit freundlichen Grüßen / Best regards
Birgitta Hauser
"Shoot for the moon, even if you miss, you'll land among the stars." (Les
Brown)
"If you think education is expensive, try ignorance." (Derek Bok)
"What is worse than training your staff and losing them? Not training them
and keeping them!"
?Train people well enough so they can leave, treat them well enough so they
don't want to.? (Richard Branson)
-----Original Message-----
From: RPG400-L <rpg400-l-bounces@xxxxxxxxxxxxxxxxxx> On Behalf Of Frank
Kolmann
Sent: Sonntag, 21. November 2021 03:38
To: rpg400-l@xxxxxxxxxxxxxxxxxx
Subject: Re: Index advisor
As I recall Reeve SQL does not use indexes that have select/omit criteria.
So I would suggest create the indexes without any selection.
Frank
On 20/11/2021 5:12 pm, Reeve wrote:
I'm reviewing the suggestions provided by the Index Advisor and some
of the key fields suggested are often blank or zero. Assuming blanks
or zeros aren't valid index entries, should I create my indexes with
WHERE clauses and exclude zeros/blanks?
Thanks,
Reeve
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