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Databases,Tables, Views, Indexing and SQL syntax
>>Hi,
>>
>>I swear I saw someone say here on the UT that 6.0 with SP3 does all its indexing in one pass now. That would be great as I am currently working on an almost 16 million record table, however - I went to the table stucture, checked four fields to index, and it went through all 4 passes (actually 8 if you count creating keys and indexing as separate)
>>
>>what's up?
>>
>
>While enhancements were made in the indexing operation, the assumption that all tags are generated in a single pass through the system is incorrect; the exact nature of the changes was not documents, but I'd suspect that the priorities for retaining data in VFP's cache probably are shifted, so that more of the data file is retained in spite of the normal preferences towards retention of index tag information. That's a pure SWAG, though; you are corect that each oindex is created and written separately and sequentially. It does seem that rebuilding a CDX takes advantage of previously-read information, which seems to reduce LAn traffic and boost performance.
>
>>TIA,
My experience matches yours. Individual index tags still get generated individually, but REINDEX seems to blast through all tags in one sweep... Of course, many developers avoid REINDEX as it cannot work correctly if the CDX header is damaged... In that case, only regenerating tags from scratch is good enough.
Rob
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