Plateforme Level Extreme
Abonnement
Profil corporatif
Produits & Services
Support
Légal
English
Performance switched with parameter
Message
De
25/09/2014 09:14:12
Mike Yearwood
Toronto, Ontario, Canada
 
 
À
24/09/2014 10:46:59
Information générale
Forum:
Microsoft SQL Server
Catégorie:
Indexation
Versions des environnements
SQL Server:
SQL Server 2012
Application:
Web
Divers
Thread ID:
01607903
Message ID:
01608257
Vues:
53
>>I would recommend dynamic SQL in any case. You'd only optimize the parts of the where clause that need it.
>
>What do you mean by "You'd only optimize the parts of the where clause that need it"?

If you create a where like

(@MinDate is null OR @MinDate < = Date) and
(@MaxDate is null OR @MaxDate > = Date) and
(@MinAmount is null OR @MinAmount > = Amount) and

SQL is doing a lot of extra work internally. If you construct the query dynamically so that in the case where @MinAmount is not passed you execute

(@MinDate is null OR @MinDate < = Date) and
(@MaxDate is null OR @MaxDate > = Date)

The optimizer will not waste time even thinking about MinAmount. :)
Précédent
Suivant
Répondre
Fil
Voir

Click here to load this message in the networking platform