"Dann Corbit" <DCorbit@connx.com> writes:
> I also do not believe that there is any value that will be the right
> answer. But a table of data might be useful both for people who want to
> toy with altering the values and also for those who want to set the
> defaults. I guess that at one time such a table was generated to
> produce the initial estimates for default values.
Sir, you credit us too much :-(. The actual story is that the current
default of 10 was put in when we first implemented stats histograms,
replacing code that kept track of only a *single* most common value
(and not very well, at that). So it was already a factor of 10 more
stats than we had experience with keeping, and accordingly conservatism
suggested not boosting the default much past that.
So we really don't have any methodically-gathered evidence about the
effects of different stats settings. It wouldn't take a lot to convince
us to switch to a different default, I think, but it would be nice to
have more than none.
regards, tom lane