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Message Posted: Tue, 24 Aug 2004 @ 11:50:03 GMT


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Subj:		Getting a random sample (sample or mod)

From:		Fred Easey

I'm sure this question's been asked many times before, but here goes.

One of my colleagues needs to get a random sample of data from a transaction line level table (1 row per item bought per transaction) from transactions made the previous week.

Should he use the sample command? (I've heard this is very inefficient). My suggestion was to use the MOD command on transaction number to get a sample, but he didn't seem to keen on this (I think he was worried that it may bias the sample somehow, although I can't personally see how thsi would happen).

Any ideas?

Fred Easey

Sainsburys