Re: raising the default default_statistics_target

Tom Lane wrote:
> Josh Berkus <josh@agliodbs.com> writes:
> > It is.   I've found that "problem" queries, especially those caused by real, 
> > uneven distribution of data, require raising statistics to 150-400 in order 
> > to fix.  This is much to high a level to assign as a default.
> 
> That's basically what's bothering me about the suggestion to increase to
> 25 --- I'm dubious that it will do any good.
> 
> > Further, in 7.5 we'll be introducing correlated stats for multi-column indexes 
> > (unless something's gone off with that?)
> 
> News to me.  It's certainly not there now.
> 
> > This will then give indexed columns "automatically" a somewhat higher
> > level of stats analysis than other columns.
> 
> That is potentially a good idea.  There's still the question of what is
> a reasonable default, though.

Do all the columns have to have the same number of statistics buckets? 
Could that stats collector adjust the number of buckets based on the
data somehow?

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