Plateforme Level Extreme
Abonnement
Profil corporatif
Produits & Services
Support
Légal
English
To Buffering or not to Buffering
Message
 
 
À
08/03/2009 13:47:43
Information générale
Forum:
Visual FoxPro
Catégorie:
Base de données, Tables, Vues, Index et syntaxe SQL
Versions des environnements
Visual FoxPro:
VFP 9 SP2
OS:
Windows XP SP2
Network:
Windows XP
Database:
Visual FoxPro
Application:
Desktop
Divers
Thread ID:
01386500
Message ID:
01386501
Vues:
104
>Hi.
>I'm writing a multi-user application and I have some questions about buffering:
>1. Is really necessary to use buffering?

You can write an application w/o it so obviously it's not necessary. However, with a buffering you only modify underlying tables when you submit changes (TABLEUPDATE()). It makes VFP table/index corruption less possible.

>2. Which buffering method is "safer"? Record/Table (Pessimist/Optimistic)?

It depends on definition of "safer". :)
The best is optimistic table buffering. It'll work with local VFP data and with remote client-server databases. And you've full control when data is updated.
The row buffering is dangerous because the data can be updated w/o your knowledge when a record pointer is moved in a view/CA cursor.
The Pessimist buffering can create contention issues and is not supported for client-server databases.
--sb--
Précédent
Suivant
Répondre
Fil
Voir

Click here to load this message in the networking platform