Andreas Seltenreich <seltenreich@gmx.de> writes:
> regression=> select (select max(result) from fdw_postgres.num_result) from tt0;
> ERROR: badly formatted node string "RESTRICTINFO :clause {NULLTEST :"...
> CONTEXT: parallel worker
Apparently, postgres_fdw is trying to store RestrictInfos in the
fdw_private field of a ForeignScan node. That won't do; those aren't
supposed to be present in a finished plan tree, so there's no readfuncs.c
support for them (and we're not adding it).
Don't know if this is a new bug, or ancient but not previously reachable.
It seems to be nearly the inverse of the problem you found yesterday,
in which postgres_fdw was stripping RestrictInfos sooner than it really
ought to. Apparently that whole business needs a fresh look.
regards, tom lane