Ibrar Ahmed <ibrar.ahmad@gmail.com> writes: > I am working on an FDW where the database does not support any operator > other than "=" in JOIN condition. Some queries are genrating the plan with > JOIN having "<" operator. How and at what stage I can stop FDW to not make > such a plan. Here is my sample query.
What exactly do you think should happen instead? You can't just tell users not to ask such a query. (Well, you can try, but they'll probably go looking for a less broken FDW.)
I know that.
If what you really mean is you don't want to generate pushed-down foreign join paths containing non-equality conditions, the answer is to just not do that. That'd be the FDW's own fault, not that of the core planner, if it creates a path representing a join it can't actually implement. You'll end up running the join locally, which might not be great, but if you have no other alternative then that's what you gotta do.
Yes, that's what I am thinking. In case of non-equality condition join them locally is
the only solution. I was just confirming.
If what you mean is you don't know how to inspect the join quals to see if you can implement them, take a look at postgres_fdw to see how it handles the same issue.
I really don't know postgres_fdw have the same issue, but yes postgres_fdw
