Re: wrong rows estimation by hash join

2023-06-10 Thread Tomas Vondra
Hi, On 6/9/23 10:36, James Pang (chaolpan) wrote: >   How does hash join estimation rows ?   pg v14, it make wrong rows > estimation then leave nest loop lef join that make poor sql plan.  A > I doubt this is specific to hashjoins, we estimate cardinality the same way for all joins (or more prec

wrong rows estimation by hash join

2023-06-09 Thread James Pang (chaolpan)
How does hash join estimation rows ? pg v14, it make wrong rows estimation then leave nest loop lef join that make poor sql plan. A -> Nested Loop Left Join (cost=171112.69..475856.90 rows=1 width=521) ->