Re: Incorrect estimates on correlated filters

"Craig Ringer" <craig@postnewspapers.com.au> writes:

> It strikes me that there are really two types of query hint possible here.
>
> One tells the planner (eg) "prefer a merge join here".
>
> The other gives the planner more information that it might not otherwise
> have to work with, so it can improve its decisions. "The values used in
> this join condition are highly correlated".

This sounds familiar:

http://article.gmane.org/gmane.comp.db.postgresql.devel.general/55730/match=hints

Plus ça change...

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  Gregory Stark
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