On Thu, 7 Mar 2024 at 23:40, Andy Fan <zhihuifan1...@163.com> wrote: > > David Rowley <dgrowle...@gmail.com> writes: > > If you don't want the planner to use the statistics for the column why > > not just do the following? > > Acutally I didn't want the planner to ignore the statistics totally, I > want the planner to treat the "Const" which probably miss optimizer part > average, which is just like what we did for generic plan for the blow > query.
I'm with Andrei on this one and agree with his "And it is just luck that you've got the right answer". I think we should fix the general problem of the planner not choosing the better index. I understand you've had a go at that before, but I didn't think fudging the costs was the right fix to coax the planner into the safer choice. I'm not personally interested in any bandaid fixes for this. I'd rather see us come up with a long-term solution that just makes things better. I also understand you're probably frustrated and just want to make something better. However, it's not like it's a new problem. The more general problem of the planner making risky choices outdates both of our time spent working on PostgreSQL, so I don't think a hasty solution that fixes some small subset of the problem is that helpful. David
