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Relative performance of views, queries & SQL-SELECT
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À
05/11/1998 17:51:47
Craig Mcclelland
Computer Fiscal Services
Sydney, Australie
Information générale
Forum:
Visual FoxPro
Catégorie:
Autre
Divers
Thread ID:
00154597
Message ID:
00155068
Vues:
22
Craig,
If you look at either the code from GENDBC or the View SQL in your view designer you will see that View = SQL and SQL = View. There is no difference in speed in running them that I know of, because a view IS SQL.

In your situation, I'd make sure the cursor was read/write (as I described in my first message) and then just scan it and format as necessary.

With large files, it will probably be faster to do the formatting after the SQL is run instead of putting functions into the SQL.

HTH
Barbara



>Barbara,
> thanks for the suggestions.
>
>I have never used views so I have very little understanding of them.
>
>I have been told by a fellow programmer that as a general rule using VIEWS is much more efficient than just running the equivalent SQL-SELECT and using the resulting cursor/table in subsequent processing (assuming that updating the base tables is not a requirement).
>
>The subsequent processing would basically be a SCAN of the entire table/view to perform some format changes etc then copying the table/view to a text file.
>
>In this sort of situation would there be any performance benefit in using a VIEW?
>
>Thanks
>Craig.
>
>
Barbara Paltiel, Paltiel Inc.
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