Walter Meester
HoogkarspelPays-Bas
Information générale
Catégorie:
Base de données, Tables, Vues, Index et syntaxe SQL
cristof,
>The result is, you are right... and I'm right. *s* VFP does a full index scan first. But then it verifies that every record in that result set really matches the condition. One exception here, as I've mentioned before, is COUNT. This command only uses the index.
I'm glad we figured it out here. The conclusion might be that in this case VFP cannot optimize this kind of queries without actually accesing the table. I would have been nice as i agree that it really can significantly improve performance.
Still standing in this case is that this kind queries are not (much) faster if you omit the deleted tag.
Maybe in the future MS will implent this kind of optimization
And, YES i also did find that count is the exception here.
Thanks,
Walter,
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