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A database challenge
Message
De
04/03/2008 01:53:15
Walter Meester
HoogkarspelPays-Bas
 
 
Information générale
Forum:
Visual FoxPro
Catégorie:
Base de données, Tables, Vues, Index et syntaxe SQL
Divers
Thread ID:
01295541
Message ID:
01298353
Vues:
34
>>
select FirstName, LastName, Address, City, State, Zip
>>     from Customers where state= 'NY' and city like '%ISLAND%'  AND ADDRESS LIKE '%BLVD%'
>>
>>Yeah, that's optimizer-friendly. But how are you going to generate it in your SP?! That looks more like SPT to me.
>
>Is LIKE %Something% optimizable??? I thought only LIKE 'Something%' optimizable.

Yes, through an index scan.. and index scan is something VFP does not have. It scans the index file for anything that matches the LIKE expression. It is more effective than a table scan, but less effective than an index seek.
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