Maxim Boguk <maxim.bo...@gmail.com> writes: > And the problem is that the cost of a custom plan ignores the cost of > planning itself (which is like 2x orders of magnitude worse than the cost > of real time partition pruning of a generic plan).
False. The estimate is evidently pretty wrong, but it's not that there is no consideration at all. See around line 1370 in src/backend/utils/cache/plancache.c. regards, tom lane