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Re: st: Relative efficiecy of merge


From   "Erik Ø. Sørensen" <sameos@mac.com>
To   statalist@hsphsun2.harvard.edu
Subject   Re: st: Relative efficiecy of merge
Date   Fri, 1 Nov 2002 12:44:22 -0500

On fredag, nov 1, 2002, at 12:22 America/Montreal, Hoetker, Glenn wrote:
One option I see is using merging A with B using the 'nokeep' option and
saving the resultant dataset as B_reduced. Since dataset B is fairly
large, however, I want this to be as efficient as possible. Is merge at
least close to the most efficient way to do this? If not, what might be
more efficient?
Have you tried and timed it? I merge files with 3-4 millions of observations regularly, and the cost of this is not so terrible. An example: it takes about 25 seconds to merge two datasets of 3 millions on a unique identifier (one dataset had 2 variables, I merged in a set with 27 variables).

Erik
--
Erik Ø. Sørensen, <http://www.geocities.com/erik_oiolf/>.
phd student (economics), Norwegian School of Economics.
currently visiting Queen's University, Kingston Ontario.

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