12 Commits (a4424c57c3da52efa212b21521abff4bf129b19e)

Author	SHA1	Message	Date
Tom Lane	b142068622	Allow CREATE FOREIGN TABLE to include SERIAL columns. ... The behavior is that the required sequence is created locally, which is appropriate because the default expression will be evaluated locally. Per gripe from Brad Nicholson that this case was refused with a confusing error message. We could have improved the error message but it seems better to just allow the case. Also, remove ALTER TABLE's arbitrary prohibition against being applied to foreign tables, which was pretty inconsistent considering we allow it for views, sequences, and other relation types that aren't even called tables. This is needed to avoid breaking pg_dump, which sometimes emits column defaults using separate ALTER TABLE commands. (I think this can happen even when the default is not associated with a sequence, so that was a pre-existing bug once we allowed column defaults for foreign tables.)	12 years ago
Tom Lane	e690b95150	Avoid retrieving dummy NULL columns in postgres_fdw. ... This should provide some marginal overall savings, since it surely takes many more cycles for the remote server to deal with the NULL columns than it takes for postgres_fdw not to emit them. But really the reason is to keep the emitted queries from looking quite so silly ...	12 years ago
Tom Lane	9cbc4b80dd	Redo postgres_fdw's planner code so it can handle parameterized paths. ... I wasn't going to ship this without having at least some example of how to do that. This version isn't terribly bright; in particular it won't consider any combinations of multiple join clauses. Given the cost of executing a remote EXPLAIN, I'm not sure we want to be very aggressive about doing that, anyway. In support of this, refactor generate_implied_equalities_for_indexcol so that it can be used to extract equivalence clauses that aren't necessarily tied to an index.	12 years ago
Tom Lane	ed3ddf918b	Introduce less-bogus handling of collations in contrib/postgres_fdw. ... Treat expressions as being remotely executable only if all collations used in them are determined by Vars of the foreign table. This means that, if the foreign server gets different answers than we do, it's the user's fault for not having marked the foreign table columns with collations equivalent to the remote table's. This rule allows most simple expressions such as "var < 'constant'" to be sent to the remote side, because the constant isn't determining the collation (the Var's collation would win). There's still room for improvement, but it's hard to see how to do it without a lot more knowledge and/or assumptions about what the remote side will do.	12 years ago
Tom Lane	50c19fc76f	Fix contrib/postgres_fdw's handling of column defaults. ... Adopt the position that only locally-defined defaults matter. Any defaults defined in the remote database do not affect insertions performed through a foreign table (unless they are for columns not known to the foreign table). While it'd arguably be more useful to permit remote defaults to be used, making that work in a consistent fashion requires far more work than seems possible for 9.3.	12 years ago
Tom Lane	0247d43dd9	Avoid row-processing-order dependency in postgres_fdw regression test. ... A test intended to provoke an error on the remote side was coded in such a way that multiple rows should be updated, so the output would vary depending on which one was processed first. Per buildfarm.	12 years ago
Tom Lane	cc3f281ffb	Fix postgres_fdw's issues with inconsistent interpretation of data values. ... For datatypes whose output formatting depends on one or more GUC settings, we have to worry about whether the other server will interpret the value the same way it was meant. pg_dump has been aware of this hazard for a long time, but postgres_fdw needs to deal with it too. To fix data retrieval from the remote server, set the necessary remote GUC settings at connection startup. (We were already assuming that settings made then would persist throughout the remote session.) To fix data transmission to the remote server, temporarily force the relevant GUCs to the right values when we're about to convert any data values to text for transmission. This is all pretty grotty, and not very cheap either. It's tempting to think of defining one uber-GUC that would override any settings that might render printed data values unportable. But of course, older remote servers wouldn't know any such thing and would still need this logic. While at it, revert commit f7951eef89, since this provides a real fix. (The timestamptz given in the error message returned from the "remote" server will now reliably be shown in UTC.)	12 years ago
Tom Lane	f7951eef89	Band-aid for regression test expected-results problem with timestamptz. ... We probably need to tell the remote server to use specific timezone and datestyle settings, and maybe other things. But for now let's just hack the postgres_fdw regression test to not provoke failures when run in non-EST5EDT environments. Per buildfarm.	12 years ago
Tom Lane	21734d2fb8	Support writable foreign tables. ... This patch adds the core-system infrastructure needed to support updates on foreign tables, and extends contrib/postgres_fdw to allow updates against remote Postgres servers. There's still a great deal of room for improvement in optimization of remote updates, but at least there's basic functionality there now. KaiGai Kohei, reviewed by Alexander Korotkov and Laurenz Albe, and rather heavily revised by Tom Lane.	12 years ago
Tom Lane	09a7cd409e	Rename postgres_fdw's use_remote_explain option to use_remote_estimate. ... The new name was originally my typo, but per discussion it seems like a better name anyway. So make the code match the docs, not vice versa.	13 years ago
Tom Lane	6da378dbc9	Fix whole-row references in postgres_fdw. ... The optimization to not retrieve unnecessary columns wasn't smart enough. Noted by Thom Brown.	13 years ago
Tom Lane	d0d75c4022	Add postgres_fdw contrib module. ... There's still a lot of room for improvement, but it basically works, and we need this to be present before we can do anything much with the writable-foreign-tables patch. So let's commit it and get on with testing. Shigeru Hanada, reviewed by KaiGai Kohei and Tom Lane	13 years ago