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> Cross-column Statistics

Holy crap I didn't even know this was feasible much less in development! Can't wait to test this out, as significant amount of my data sets have these kinds of relationships.

Parallel query will also be great for certain queries I do regularly. Been looking forward to this!

Thank you Thank you to all the devs that had a part of this!

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Cross-column statistics are one of my favorites. The way Postgres 10 handles it is really a _huge_ advancement that addresses a painful edge case that has been around for ages.

https://blog.2ndquadrant.com/pg-phriday-crazy-correlated-col...

To be honest, skewed data problem can be addressed with partitioning in many cases.

Cross-column statistics is a great feature nevertheless.

Yes, but partitioning also has a number of limitations that may be quite undesirable. Like inability to create UNIQUE constraints or primary keys, for example.

More importantly it doesn't help at all with cross-column correlations. It can help with skew in between various rows though.

Thanks, I'm happy it got into PG10 too. Just to make it very clear - the current implementation is fairly simple, and may not be smart enough to deal with more complicated dependencies between columns. Hopefully that will be improved in PG11.

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