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Base de données, Tables, Vues, Index et syntaxe SQL
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>>>>>>I have install SQLExpress2008 on a WS2003 with 2 Gb RAM (development machine)
>>>>>>
>>>>>>When I run a query against a table with 100.000 records from the Microsoft SQl Server Managent studio:
>>>>>> [ Select top 1000 from sometable ]
>>>>>>It returns the results in less than a second.
>>>>>>
>>>>>>But when I run the same query from VFP
>>>>>> [ sqlexec(nHandle, "Select top 1000 from sometable ", "cur") ]
>>>>>>It takes for ever, more than 15 seconds.
>>>>>>What is the problem ?
>>>>>
>>>>>Where is your ORDER BY clause in the above statement? As far as I recall, TOP is not optimizable (I'll double check).
>>>>
>>>>Same performance WITH/WITHOUT order by clause
>>>
>>>If you're using TOP clause you MUST specify ORDER BY. What is your SQL Server version? Check the message I pointed you too and Kevin Goff's suggestion - may be worth a try.
>>
>>Same performance WITH/WITHOUT order by clause
>>But why this performance difference between SSMStudio and VFP client connection ?
>
>Try
>
>select top 1000 ID from Sometable Order by ID - what would be the performance?
>
>Try also
>
>select myFields from SomeTable tablesample (1000 rows)
No difference. As I said before why the differnce between the SSMStudio and the VFP client with ODBC connection ?
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