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Inserting date into sql or firebird;What is .t. value in
Message
De
07/10/2005 14:59:08
Dorin Vasilescu
ALL Trans Romania
Arad, Roumanie
 
Information générale
Forum:
Visual FoxPro
Catégorie:
Client/serveur
Divers
Thread ID:
01050571
Message ID:
01057310
Vues:
13
Hi

About the cbo, I will send a sample about how to make it look like "inside" grid

>
>Yup and the better thing is I did not have to issue any SPT to set indexes sort of. I had a SPT which worked okay. I then indexed the data on the same ORDER BY and whoosh it speeded up just like that.

It depends. On a server with a lot of memory and small/medium result set, ORDER BY without an index to be used by optimiser for sorting will be always faster than with the index.
The explanation is that the I/O overhead of reading index and then rows in index order is higher than selecting rows and then sort in memory.

>
>>A SET STATISTICS INDEX {index} can be useful from time to time, specially after a bulk load.
>
>There now, you will have to explain, is this a sort of REINDEX?

No. Firebird mantains a selectivity computation ( index entries/distinct rows ) to decide if an index is OK to be used by query optimiser. SET STATISTICS recalculate selectivity.

ALTER INDEX INACTIVE
ALTER INDEX ACTIVE
rebuild indices (also recompute selectivity).
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