Plateforme Level Extreme
Abonnement
Profil corporatif
Produits & Services
Support
Légal
English
Which statement is 'Better'
Message
De
12/09/2005 12:32:59
 
 
Information générale
Forum:
Visual FoxPro
Catégorie:
Codage, syntaxe et commandes
Versions des environnements
Visual FoxPro:
VFP 6
Divers
Thread ID:
01048319
Message ID:
01048825
Vues:
20
>Rich,
>
>You might also consider moving your loc.state='OR' up into the JOIN.

This leads me to some questions on WHERE vs JOIN. Since that's off-topic, I'll be opening another thread about it shortly.

>
>In SQL server you should avoid SELECT * in a query when none of the fields are actually used or you don't need all of them, you force a read of the data page even if can determine the result only from reading index pages. I/O is slow. Use SELECT 'X' instead.
>

Thanks for the info.

Since you specified SQL Server, I assume it doesn't matter if the query runs against Fox tables????

When you say SELECT 'X' I'm assuming you mean 'X' to be a literal rather than SELECT somefield???

The application I support uses DB2 rather than SQL server. Do you know if the same constraints apply?

It isn't worth investing time to investigate (unless you're interested in the topic yourself) since the modules involved run an overnight process and it doesn't matter if it takes an extra 10 or 15 minutes to complete (and I think we're talking seconds of difference rather than minutes).

Thanks for your response..........Rich
Précédent
Suivant
Répondre
Fil
Voir

Click here to load this message in the networking platform