Thread

Re: Import Statistics in postgres_fdw before resorting to sampling.

Etsuro Fujita <etsuro.fujita@gmail.com> — 2025-12-15T10:01:44Z

On Mon, Dec 15, 2025 at 5:01 AM Corey Huinker <corey.huinker@gmail.com> wrote:

>> Ah, I mean the case where the foreign table is an inheritance parent
>> on the *local* side.  In that case, the return would cause us to skip
>> the recursive ANALYZE (i.e., do_analyze_rel() with inh=true), leading
>> to no inherited stats.  I agree that the case is minor, but I don't
>> think that that's acceptable.

> When such a corner case occurs (stats import configured to true, but table is an inheritance parent), should we raise an error, or raise a warning and return false on the CanImportStats() call? I guess the answer may depend on the feedback we get.

As mentioned upthread, the FDW API that I proposed addresses this
issue; even in such a case it allows the FDW to import stats, instead
of doing the normal non-recursive ANALYZE, and then do the recursive
ANALYZE, for the inherited stats.

Best regards,
Etsuro Fujita