Re: [HACKERS] Reg external sorting alogrithm

[Tom Lane]

Praveen Kumar N <[EMAIL PROTECTED]> writes:
>   can anybody tell me what is the computational complexity of 
> external sorting algorithm used by postgres in terms of time and space.

See the comments at the head of tuplesort.c:
http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/utils/sort/tuplesort.c

regards, tom lane

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[HACKERS] Reg external sorting alogrithm

[Praveen Kumar N]

Hi,
	can anybody tell me what is the computational complexity of 
external sorting algorithm used by postgres in terms of time and space.
And one more question is how does # of DISK I/O's vary by varying jsf and 
size of data while using external sorting algorithms to sort(I mean is it 
like linear relation ship or in terms of logarithmic function).


thanks in anticipation.

Regards,
 N Praveen Kumar


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