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Date: Mon, 28 Jul 2003 12:25:08 -0400
From: Hyman Rosen <hyrosen@mail.com>
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Subject: Re: sorting large numbers of large records
References: <bg3fgg$qig$1@grapevine.wam.umd.edu>
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Date: 2003-07-28T12:25:08-04:00
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You should read Knuth's Sorting and Searching.
The classic way to do this is to read as many records
from the file as you can fit in memory, sort them, and
write them back out to another file. Keep doing this
until you have sorted all of your original records.
Now merge all the sorted subfiles together. You do that
by reading a record from each subfile, writing out the
smallest, and reading a new record from the file which
provided the record just written.