Re: Look at all paths?

On 12/29/21 5:07 AM, Chris Cleveland wrote:
> I'm developing a new index access method. Sometimes the planner uses it 
> and sometimes it doesn't. I'm trying to debug the process to understand 
> why the index does or doesn't get picked up.
> 
> Is there a way to dump all of the query plans that the planner 
> considered, along with information on why they were rejected? EXPLAIN 
> only gives info on the plan that was actually selected.

You can enable OPTIMIZER_DEBUG option. Also the gdbpg code [1] makes our 
work much easier, sometimes.

[1] https://github.com/tvondra/gdbpg

-- 
regards,
Andrey Lepikhov
Postgres Professional