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Performance re-index before/after defragmentation?
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Information générale
Forum:
Visual FoxPro
Catégorie:
Base de données, Tables, Vues, Index et syntaxe SQL
Divers
Thread ID:
00748158
Message ID:
00748237
Vues:
27
>>>>Has any solid research been done in reference to performance after re-indexing before verses after defragmentation of the drive?
>>>
>>>In addition to degragmentation, you should also consider re-ordering the table to its "natural" order. For example, if you have a table that's ordered by one particular field, re-building that table so that the records are in that order can yield a reduction of index size of up to 20%.
>>
>>How would this affect the case - the usual case, I believe - where there are several indices, on differente fields or expressions?
>
>I haven't yet tested to see. However, I would think that at least some reduction in size would occur simply because the main index would take up less size.

Yea, that's a tough one. It seems logical that there would be a reduction, but that might also depend on the length of the sorted key versus how DISordered longer keys became by the operation.
But I'd still say myself that rebuilding the table in its **most frequently used** key order should pay dividends at least in terms of overall response compared to just copying/reindexing willy-nilly.

cheers
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