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Codage, syntaxe et commandes
Jim,
how can the SELECT know that a function included does not change its value
(it is after all a function call)
and though usually DATE() shouldn't change during the query (btw as Paul
stated what happens if you run the query very close to midnight..)
I don't think it is stupid to re-evaluate them
Arnon
>George,
>
>Pardon my English, but that would be awfully stupid of SQL - to run the
>Date function for every record in the input. What makes you so sure it
>would do so??
>
>Enquiring minds need to know.
>
>regards,
>Jim N
>
>>>Is there any optimization difference in the following:
>>>
>>>SELECT FIELD FROM TABLE WHERE FIELDDATE=DATE() INTO CURSOR TEMP
>>>
>>>OR
>>>
>>>ldDate=DATE()
>>>SELECT FIELD FROM TABLE WHERE FIELDDATE=ldDate INTO CURSOR TEMP
>>
>>Michel,
>>
>>I'm not sure about differences in optimization, but the latter query
>should execute faster. The reason being that the date function will have to
>be called and it will have to return its value for every record in the
>table. In the latter case, it simply a straight comparison.
>>
>>George
>
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