> Bruce Momjian writes:
> 
> > No, we have no ability to randomly pick rows to use for estimating
> > statistics.  Should we have this ability?
> 
> How's reading a sufficiently large fraction of random rows going to be
> significantly faster than reading all rows?  If you're just going to read
> the first n rows then that isn't really random, is it?

Ingres did this too, I thought.  You could specify a certain number of
random rows, perhaps 10%.  On a large table, that is often good enough
and much faster.  Often 2% is enough.

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  Bruce Momjian                        |  http://candle.pha.pa.us
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