On Mon, Dec 15, 2014 at 3:40 AM, Shigeru Hanada <shigeru.han...@gmail.com> wrote: > I'm working on $SUBJECT and would like to get comments about the > design. Attached patch is for the design below.
I'm glad you are working on this. > 1. Join source relations > As described above, postgres_fdw (and most of SQL-based FDWs) needs to > check that 1) all foreign tables in the join belong to a server, and > 2) all foreign tables have same checkAsUser. > In addition to that, I add extra limitation that both inner/outer > should be plain foreign tables, not a result of foreign join. This > limiation makes SQL generator simple. Fundamentally it's possible to > join even join relations, so N-way join is listed as enhancement item > below. It seems pretty important to me that we have a way to push the entire join nest down. Being able to push down a 2-way join but not more seems like quite a severe limitation. -- Robert Haas EnterpriseDB: http://www.enterprisedb.com The Enterprise PostgreSQL Company -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
