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Funny: When a equal can to be not equal
Message
De
11/04/2005 13:16:45
 
 
Information générale
Forum:
Visual FoxPro
Catégorie:
Base de données, Tables, Vues, Index et syntaxe SQL
Versions des environnements
Visual FoxPro:
VFP 9
Divers
Thread ID:
01003001
Message ID:
01003432
Vues:
17
>Fabio,
>
>Comment: Why would someone, besides you, actually think it was useful to build an index on a table that had no dependence on any of the data in the table?
>

A simple example for you:
* fill a table/cursor
* Now you want a random uniform scan:
INDEX RAND() TAG T_RAND
SET ORDER TO T_RAND
SCAN
...
ENDSCAN
* repeatable! regardless from the UPDATE/REPLACE operations
* none update overload!
* none field used!
REPLICATE ALL .....
* next scan is the same of previous scan
SET ORDER TO T_RAND
SCAN
...
ENDSCAN
* with a simple way for change the order!
REINDEX
With DATE()/DATETIME() is possible do more complex operations.
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