Re: MAX/MIN optimization via rewrite (plus query rewrites

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От Mark Kirkwood
Тема Re: MAX/MIN optimization via rewrite (plus query rewrites
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Msg-id 41931C6A.4030401@coretech.co.nz
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Ответ на Re: MAX/MIN optimization via rewrite (plus query rewrites generally)  ("John Hansen" <john@geeknet.com.au>)
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Probably for a small table, where the machinery of reading the index, 
followed by checking the table for non-visible tuples is more costly 
than just scanning the table!


regards

Mark

John Hansen wrote:

>Why not just change the function all together to 'select $1 from $2
>order by $1 desc limit 1;'
>
>Is there ANY situation where max(col) as it is, would be faster?
>
>... John
>  
>


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