gen4: Add hash join primitive and planning#9140

Merged

systay merged 40 commits intovitessio:mainfrom planetscale:hash-join

Nov 22, 2021

+2,526-458

Commits on Nov 4, 2021

Commits on Nov 13, 2021

change type of hashcodes, and start testing
systay
committed

Commits on Nov 15, 2021

Commits on Nov 16, 2021

Commits on Nov 17, 2021

Commits on Nov 22, 2021

test: use the hash join hint in the end to end test
systay
committed
feat: turn off the cost check before using hash joins. we'll just rely on the hint for now
systay
committed
refactor: move collation check inside canHashJoin function
systay
committed