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Base de données, Tables, Vues, Index et syntaxe SQL
>Believer may be a bit too strong, but I'm getting nearer to your opinion.
Well, I think we can agree that SOMETHING is going on here that isn't quite what is expected of Rushmore.
>If you indexed your table on a particular field, in other words had a CDX that
>contained only one tag, how long would it take to copy it from the network to >your machine? I'm asking that just to clarify how fast can your machine can
I don't have the hardware or the data here, it's at a site in another state. I did the testing while on site. I'm answering some of this from memory. The CDX contained several tags in it and generally the CDX's are about 2/3 the size of the matching DBF. Perhaps a bloated CDX is part of the problem, but I don't have much choice since this is a research tool and the end-user wants to look stuff up a million different ways. The tables I was testing were, on the average, about 300 Meg, and the CDX's were about 200 Meg.
I chose my test records by opening a table without an index set and just went to the bottom few records.
>read the CDX into its memory. If you then used the table in SHARED mode and
>SET ORDER TO TheField, and did a locate to a record that is near the bottom of
>the index, you are saying that it may take 30 minutes to LOCATE the record,
>which seems to you, (and me too), like VFP is having to read the entire table,
>not just a CDX file. Right? I would expect your LOCATE to take the time it
Sound like what I did, but I didn't really consider the record to be at the end of the CDX, I just chose records at the end of the DBF (which probably works out about the same).
>BTW, I don't have VFP 3.0, but 2.6 and 6.00.8 both seem to work the same way.
I use FoxPro 2.6, VFP 3.01b, VFP 5.0 and VFP 6.0 and the indexing stuff all appears to have the same performance as far as I can tell.
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