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Is this how VFP works?
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Information générale
Forum:
Visual FoxPro
Catégorie:
Autre
Versions des environnements
Visual FoxPro:
VFP 9 SP1
Divers
Thread ID:
01202551
Message ID:
01202566
Vues:
8
>I was at the user group meeting last week and one of the guys there (seemed to be very knowledgeable) said the following:
>
>When you use SQL Select command and even if your WHERE clause is getting just one record (WHERE MYPK = nPk), VFP downloads the entire table (even if it has 1000,000 records) to the local drive and then selects the desired record from the local drive.
>
>Is this true?

It would be only true if query is not optimizable. Rememeber that all processing is done on the local PC. VFP has to pull all the data required to process localy. In case of optimizable query, only relevant part of table indexes will be read by VFP to determine the record(s) to return.
--sb--
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