RE: Embedded sql without index faster than with index

-----Message d'origine-----
De : rpg400-l-bounces@xxxxxxxxxxxx
[mailto:rpg400-l-bounces@xxxxxxxxxxxx] De la part de Birgitta Hauser
Envoyé : mardi 8 mars 2011 14:56
À : 'RPG programming on the IBM i / System i'
Objet : AW: Embedded sql without index faster than with index

... but you are not using the same data?
The optimizer may use different access paths/indexes or a
table scan instead of an index access when accessing
different data (even with the same program).
That's often a problem for software manufacturers to provide
the correct/optimal indexes

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!"

-----Ursprüngliche Nachricht-----
Von: rpg400-l-bounces@xxxxxxxxxxxx
[mailto:rpg400-l-bounces@xxxxxxxxxxxx] Im Auftrag von David FOXWELL
Gesendet: Tuesday, 08. March 2011 13:13
An: RPG programming on the IBM i / System i
Betreff: RE: Embedded sql without index faster than with index


Two versions of the same program, one running slower than the other.
Recompiled the slow runner and it now performs like the
faster version.
Smells like a bug.








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