Re: "between" is using index but "like" is not

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От Gaetano Mendola
Тема Re: "between" is using index but "like" is not
Дата
Msg-id 412D4205.6000406@bigfoot.com
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Ответ на Re: "between" is using index but "like" is not  (Josh Berkus <josh@agliodbs.com>)
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Josh Berkus wrote:

> Jesper,
>
>
>>Why doesn't it use an index on the "like" operator when it doesn't contain
>>a wildcard in the beginning of the pattern?
>
>
> How many rows are there in the table?   What happens if you force an index
> scan on the 2nd query?  Is this ASCII text or UNICODE text?
>
> Normally LIKE 'xxx%' does use an index if it's useful, so there is something
> else going on here.

Shall not him define an index with the right operator class in order to be used
with the like operator ?



Regards
Gaetano Mendola



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