Re: Add semi-join pushdown to postgres_fdw

Hi.

Tomas Vondra писал 2023-01-19 20:49:
> I took a quick look at the patch. It needs a rebase, although it
> applies
> fine using patch.
>
> A couple minor comments:
>
> 1) addl_conds seems a bit hard to understand, I'd use either the full
> wording (additional_conds) or maybe extra_conds

Renamed to additional_conds.

>
> 2) some of the lines got quite long, and need a wrap
Splitted some of them. Not sure if it's enough.

>
> 3) unknown_subquery_rels name is a bit misleading - AFAIK it's the rels
> that can't be referenced from upper rels (per what the .h says). So
> they
> are known, but hidden. Is there a better name?

Renamed to hidden_subquery_rels. These are rels, which can't be referred
to from upper join levels.

>
> 4) joinrel_target_ok() needs a better comment, explaining *when* the
> reltarget is safe for pushdown. The conditions are on the same row, but
> the project style is to break after '&&'.

Added comment. It seems to be a rephrasing of lower comment in
joinrel_target_ok().

--
Best regards,
Alexander Pyhalov,
Postgres Professional