postgresql/contrib/postgres_fdw
Tom Lane 215824f918 In postgres_fdw, don't try to ship MULTIEXPR updates to remote server.
In a statement like "UPDATE remote_tab SET (x,y) = (SELECT ...)",
we'd conclude that the statement could be directly executed remotely,
because the sub-SELECT is in a resjunk tlist item that's not examined
for shippability.  Currently that ends up crashing if the sub-SELECT
contains any remote Vars.  Prevent the crash by deeming MULTIEXEC
Params to be unshippable.

This is a bit of a brute-force solution, since if the sub-SELECT
*doesn't* contain any remote Vars, the current execution technology
would work; but that's not a terribly common use-case for this syntax,
I think.  In any case, we generally don't try to ship sub-SELECTs, so
it won't surprise anybody that this doesn't end up as a remote direct
update.  I'd be inclined to see if that general limitation can be fixed
before worrying about this case further.

Per report from Lukáš Sobotka.

Back-patch to 9.6.  9.5 had MULTIEXPR, but we didn't try to perform
remote direct updates then, so the case didn't arise anyway.

Discussion: https://postgr.es/m/CAJif3k+iA_ekBB5Zw2hDBaE1wtiQa4LH4_JUXrrMGwTrH0J01Q@mail.gmail.com
2020-01-26 14:31:08 -05:00
..
expected In postgres_fdw, don't try to ship MULTIEXPR updates to remote server. 2020-01-26 14:31:08 -05:00
sql In postgres_fdw, don't try to ship MULTIEXPR updates to remote server. 2020-01-26 14:31:08 -05:00
.gitignore Add postgres_fdw contrib module. 2013-02-21 05:27:16 -05:00
connection.c Update copyrights for 2020 2020-01-01 12:21:45 -05:00
deparse.c In postgres_fdw, don't try to ship MULTIEXPR updates to remote server. 2020-01-26 14:31:08 -05:00
Makefile Split all OBJS style lines in makefiles into one-line-per-entry style. 2019-11-05 14:41:07 -08:00
option.c Only superuser can set sslcert/sslkey in postgres_fdw user mappings 2020-01-13 18:08:09 +10:30
postgres_fdw--1.0.sql Add postgres_fdw contrib module. 2013-02-21 05:27:16 -05:00
postgres_fdw.c Update copyrights for 2020 2020-01-01 12:21:45 -05:00
postgres_fdw.control Add postgres_fdw contrib module. 2013-02-21 05:27:16 -05:00
postgres_fdw.h Update copyrights for 2020 2020-01-01 12:21:45 -05:00
shippable.c Update copyrights for 2020 2020-01-01 12:21:45 -05:00