56 Commits (9c5f67fd6256246b2a788a8feb1d42b79dcd0448)

Author	SHA1	Message	Date
Tom Lane	5b86fedfb5	Document cross-version compatibility issues for contrib/postgres_fdw. ... One of the use-cases for postgres_fdw is extracting data from older PG servers, so cross-version compatibility is important. Document what we can do here, and further annotate some of the coding choices that create compatibility constraints. In passing, remove one unnecessary incompatibility with old servers, namely assuming that we didn't need to quote the timezone name 'UTC'.	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	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	6d06049493	Adjust postgres_fdw's search path handling. ... Set the remote session's search path to exactly "pg_catalog" at session start, then schema-qualify only names that aren't in that schema. This greatly reduces clutter in the generated SQL commands, as seen in the regression test changes. Per discussion. Also, rethink use of FirstNormalObjectId as the "built-in object" cutoff --- FirstBootstrapObjectId is safer, since the former will accept objects in information_schema for instance.	13 years ago
Tom Lane	54a2786835	Need to decorate XactIsoLevel as PGDLLIMPORT for postgres_fdw. ... Per buildfarm.	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