Re: Sort time

Hi,

Tom Lane wrote:

> Josh Berkus <josh@agliodbs.com> writes:
> > Here's a question: is the total size of the column a good indicator of the
> > sort_mem required?   Or does the rowsize affect it somehow?
>
> It will include all the data that's supposed to be output by the sort...
> both the key column(s) and the others.
>

Hmm it is not clear for me.Let we have all data.
If I make sort by S.OP ( it is INT) it take < 6 sek for sort.
I think we move all this data anly the number of comparation is by INT. I think
the number of comparation
is ~ n * ln(n).
If we sort by S.IDS_xxx we have also n*ln(n) comparations but in
varchar(string).
I don't think that it can take 50 sek.

Is it not so?

regards,
ivan.

>                         regards, tom lane
>
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