Re: Selecting K random rows - efficiently!

[cluster <skrald@xxxxxxxxxx>]

Another way to look at the problem is: How do I sample a subset of size 
K efficiently? A query like

   SAMPLE 1000 OF
   (SELECT * FROM mydata WHERE <some condition>)

should return 1000 random rows from the select statement so that two 
consecutive evaluations of the query would only with very little 
probability return the same 1000 rows.
(Yes, I know that "SAMPLE 1000 OF" is not valid SQL)

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