Tom,
> We have also talked about solving the multi-column statistics problem
> (which, at its core, is "which combinations of columns are worth
> accumulating stats for?" --- you can't possibly store stats for every
> combination!) by having what would amount to hints from the DBA saying
> "keep stats for these combinations".
We could start just by keeping stats for multiple columns which are indexed
together. That doesnt' cover everything (thanks to bitmapping) but would
cover many cases.
--
--Josh
Josh Berkus
PostgreSQL @ Sun
San Francisco