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SSMS recommends index but do not use it
Message
De
18/06/2015 10:18:04
 
Information générale
Forum:
Microsoft SQL Server
Catégorie:
Autre
Versions des environnements
SQL Server:
SQL Server 2012
Application:
Web
Divers
Thread ID:
01621109
Message ID:
01621134
Vues:
39
>Yep. And just because it happens to use the index now, as time goes on and data is added or the statistics change, it can decide to use another index. What I've done in some cases is to grab a copy of the actual query execution plan (both as a screenshot and XML) so I have something to compare against if a query suddenly starts behaving differently than it did in the past.
>
>You can also add index hints to the query to force it to use a specific index, ex.
>
>
>SELECT SomeField
>  FROM SomeTable WITH(INDEX(NameOfIndex))
> WHERE SomeField = 4
>
>
>Just realize that can cause it's own issues (same reasons - the data changes, more records are added) and suddenly that isn't really the best index to use anymore. But since you're forcing it, the query analyzer can't use anything else.

Yes, exactly, forcing it could create another ball game.

I use that at one place for big calculation but in general, WITH INDEX should not be used.
Michel Fournier
Level Extreme Inc.
Designer, architect, owner of the Level Extreme Platform
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