Re: 7.4 Wishlist

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От
Magnus Naeslund(f)
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Re: 7.4 Wishlist
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063201c29a42$316532f0$f80c0a0a@mnd
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Re: 7.4 Wishlist "Stephen L." <jleelim@hotmail.com>
Re: 7.4 Wishlist Greg Copeland <greg@CopelandConsulting.Net>
Christopher Kings-Lynne  wrote:
>> Mysql is planning on making this work:
>>
>>  SELECT id, @a:=COUNT(*), SUM(sum_col)/@a FROM table_name GROUP BY
>> id.
>>
>> Do we have anything like it (After a discussion with Tom i figure
>> no). User variables is nice, especially in these kind of queries.
>
> Well of course they have to make that work - they don't have
> subselects :P
>
> Chris

Yeah, but there is a point about running count(*) one time too many.
Say if i would like to get a prettyprinting query like this:

SELECT id, @a:=COUNT(*), sum_col::text||'/'@a::text FROM table_name;

That would be DAMN expensive doing with a subselect:

SELECT id, sum_col||'/'||(select COUNT(*) from tabe_name) FROM
table_name;

I know this example suck eggs, but you get the point where it hurts,
right?

Magnus - sorry for the dupe, chris


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