Level Extreme platform
Subscription
Corporate profile
Products & Services
Support
Legal
Français
Set filter to not empty()
Message
From
06/01/2014 06:43:23
Metin Emre
Ozcom Bilgisayar Ltd.
Istanbul, Turkey
 
 
To
02/01/2014 21:43:14
Thomas Ganss (Online)
Main Trend
Frankfurt, Germany
General information
Forum:
Visual FoxPro
Category:
Coding, syntax & commands
Environment versions
Visual FoxPro:
VFP 9 SP2
OS:
Windows Server 2012
Network:
Windows 2008 Server
Database:
MS SQL Server
Application:
Web
Miscellaneous
Thread ID:
01591204
Message ID:
01591389
Views:
83
I read help and seem I got wrong binary indexes.

thank you for clarification...



>With empty() you have only the 2 states as results. That also means the index has low selectivity, which translates in relatively bad performance of the index - sometimes it is worth than having no index at all. A binary index is ONLY the resulting bitmap of rushmore, which means much less data transfer between data store and client CPU, resulting to nearly always shortest time. So IF you need an index / filter for such a state, ALWAYS add binary clause if using a vfp version supporting it.
>
>HTH
>
>thomas
>
>>binary index? why? how can a binary index help him?
>>
>>>and if you index the condition be sure to define as binary...
>>>
>>>>Thank you Marcia.
>>>>
>>>>It was a grid problem. Not set filter.
>>>>
>>>>Moises
>>>>
>>>>
>>>>>Something like: Set filter to not empty(myfield).
>>>>>
>>>>>But it does not work because this is not the correct syntax.

>>>>>
>>>>>It works for me.
>>>>>
>>>>>
>>>>>Use MyTable in 0
>>>>>Select MyTable
>>>>>Set Filter To Not Empty(MyFierld)
>>>>>Go Top
>>>>>Browse Normal
>>>>>
>>>>>
>>>>>Happy New Year to you too..
Previous
Reply
Map
View

Click here to load this message in the networking platform