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Is it possible to speed this loop and/or SQL up?
Message
De
21/03/2005 08:36:24
Hilmar Zonneveld
Independent Consultant
Cochabamba, Bolivie
 
 
À
21/03/2005 08:31:39
Information générale
Forum:
Visual FoxPro
Catégorie:
Base de données, Tables, Vues, Index et syntaxe SQL
Versions des environnements
Visual FoxPro:
VFP 7 SP1
OS:
Windows XP SP2
Database:
Visual FoxPro
Divers
Thread ID:
00997258
Message ID:
00997793
Vues:
10
>Two minds, one thought. That's why I asked Terry for the index expression.

Perhaps I should have added WHY this might be faster. I am sure that you, Tore, know this already:

A search on a combined expression, in an index, will be more discriminating - less records have to be fetched from an index.

With several searches on individual fields, combined with AND, before getting the perhaps only record, or the few records, that match the expression, lots of index keys have to be fetched from the corresponding indices, and combined, to determine the correct record(s). This may take quite a while.
Difference in opinions hath cost many millions of lives: for instance, whether flesh be bread, or bread be flesh; whether whistling be a vice or a virtue; whether it be better to kiss a post, or throw it into the fire... (from Gulliver's Travels)
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