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Set filter to not empty()
Message
De
03/01/2014 12:10:33
Mike Yearwood
Toronto, Ontario, Canada
 
 
À
02/01/2014 21:53:05
Information générale
Forum:
Visual FoxPro
Catégorie:
Codage, syntaxe et commandes
Versions des environnements
Visual FoxPro:
VFP 9 SP2
OS:
Windows Server 2012
Network:
Windows 2008 Server
Database:
MS SQL Server
Application:
Web
Divers
Thread ID:
01591204
Message ID:
01591292
Vues:
83
>first time I see you giving out dangerous advice!
>
>lcTab = CHR(9)
>lcSpc = CHR(32)
>? lcTab=lcSpc
>? EMPTY(lcTab)=EMPTY(lcSpc)
>
>and yes, if I KNOW the data, I use your approach as well, but have set up a mental checkpoint for myself ;-)

I don't see how that applies. I advised him not to use empty at all. If there is a tab character in a field, I would not consider it empty.

>
>regards
>
>thomas
>
>>EMPTY() is not Rushmore optimizable unless you add an INDEX ON EMPTY(myfield). That is a non-discriminating index. If you already have another index on myfield like this... INDEX ON UPPER(myfield) TAG xmyfield
>>
>>then the following will work.
>>
>>lcSpaces=space(len(myfield))
>>SET FILTER TO UPPER(myfield) # m.lcSpaces
>>
>>You won't need a new index and it will optimize.
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