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Is there a speed difference between filter and seek ?
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À
19/09/2000 01:51:23
Information générale
Forum:
Visual FoxPro
Catégorie:
Codage, syntaxe et commandes
Divers
Thread ID:
00417902
Message ID:
00418515
Vues:
35
>>Filter expressions are optimizable if the index exactly matches the filter expression but a SEEK is always going to be faster.
>>
>>Try the following:
>>select appur
>>seek the_ident
>>scan while ident = the_ident
>>   * do stuff
>>endscan
>
>>The WHILE inhibits the SCANs behavior of going to the top.
>
>...and keeps the SCAN from going all the way to the bottom....

Unless, of course, the last record in the "the_ident" group happens to be the last record in the table. ;-)
Larry Miller
MCSD
LWMiller3@verizon.net

Accumulate learning by study, understand what you learn by questioning. -- Mingjiao
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