Re: polyphase merge? - Mailing list pgsql-hackers

From Tom Lane
Subject Re: polyphase merge?
Date
Msg-id 2316.1233760846@sss.pgh.pa.us
Whole thread Raw
In response to Re: polyphase merge?  (Don Marvick <donmarvick@gmail.com>)
Responses Re: polyphase merge?  (Don Marvick <donmarvick@gmail.com>)
List pgsql-hackers
Don Marvick <donmarvick@gmail.com> writes:
> Since nobody replied, I would give it a try. I am going to implement the
> merge pattern described in Knuth Page 365 (5.4.9), essentially it is as
> follow:
> - create initial runs using replacement selection (basically this is as in
> the current implementation)
> - add enough dummy runs of size 0 so that the number of sorted run minus one
> can be divided by k-1 (k is merge fan in)
> - repetitively merge k smallest runs until only 1 run left

How is this better than, or even different from, what is there now?
        regards, tom lane


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