5 Commits (c7f0b28c7a67a8602c65d6b38d40b38d07548fbd)

Author	SHA1	Message	Date
Andres Freund	168d5805e4	Add support for INSERT ... ON CONFLICT DO NOTHING/UPDATE. ... The newly added ON CONFLICT clause allows to specify an alternative to raising a unique or exclusion constraint violation error when inserting. ON CONFLICT refers to constraints that can either be specified using a inference clause (by specifying the columns of a unique constraint) or by naming a unique or exclusion constraint. DO NOTHING avoids the constraint violation, without touching the pre-existing row. DO UPDATE SET ... [WHERE ...] updates the pre-existing tuple, and has access to both the tuple proposed for insertion and the existing tuple; the optional WHERE clause can be used to prevent an update from being executed. The UPDATE SET and WHERE clauses have access to the tuple proposed for insertion using the "magic" EXCLUDED alias, and to the pre-existing tuple using the table name or its alias. This feature is often referred to as upsert. This is implemented using a new infrastructure called "speculative insertion". It is an optimistic variant of regular insertion that first does a pre-check for existing tuples and then attempts an insert. If a violating tuple was inserted concurrently, the speculatively inserted tuple is deleted and a new attempt is made. If the pre-check finds a matching tuple the alternative DO NOTHING or DO UPDATE action is taken. If the insertion succeeds without detecting a conflict, the tuple is deemed inserted. To handle the possible ambiguity between the excluded alias and a table named excluded, and for convenience with long relation names, INSERT INTO now can alias its target table. Bumps catversion as stored rules change. Author: Peter Geoghegan, with significant contributions from Heikki Linnakangas and Andres Freund. Testing infrastructure by Jeff Janes. Reviewed-By: Heikki Linnakangas, Andres Freund, Robert Haas, Simon Riggs, Dean Rasheed, Stephen Frost and many others.	11 years ago
Andres Freund	d6fa44fce7	Add skip-empty-xacts option to test_decoding for use in the regression tests. ... The regression tests for contrib/test_decoding regularly failed on postgres instances that were very slow. Either because the hardware itself was slow or because very expensive debugging options like CLOBBER_CACHE_ALWAYS were used. The reason they failed was just that some additional transactions were decoded. Analyze and vacuum, triggered by autovac. To fix just add a option to test_decoding to only display transactions in which a change was actually displayed. That's not pretty because it removes information from the tests; but better than constantly failing tests in very likely harmless ways. Backpatch to 9.4 where logical decoding was introduced. Discussion: 20140629142511.GA26930@awork2.anarazel.de	11 years ago
Andres Freund	626bfad6cc	Fix decoding of consecutive MULTI_INSERTs emitted by one heap_multi_insert(). ... Commit 1b86c81d2d fixed the decoding of toasted columns for the rows contained in one xl_heap_multi_insert record. But that's not actually enough, because heap_multi_insert() will actually first toast all passed in rows and then emit several *_multi_insert records; one for each page it fills with tuples. Add a XLOG_HEAP_LAST_MULTI_INSERT flag which is set in xl_heap_multi_insert->flag denoting that this multi_insert record is the last emitted by one heap_multi_insert() call. Then use that flag in decode.c to only set clear_toast_afterwards in the right situation. Expand the number of rows inserted via COPY in the corresponding regression test to make sure that more than one heap page is filled with tuples by one heap_multi_insert() call. Backpatch to 9.4 like the previous commit.	11 years ago
Andres Freund	1b86c81d2d	Fix decoding of MULTI_INSERTs when rows other than the last are toasted. ... When decoding the results of a HEAP2_MULTI_INSERT (currently only generated by COPY FROM) toast columns for all but the last tuple weren't replaced by their actual contents before being handed to the output plugin. The reassembled toast datums where disregarded after every REORDER_BUFFER_CHANGE_(INSERT|UPDATE|DELETE) which is correct for plain inserts, updates, deletes, but not multi inserts - there we generate several REORDER_BUFFER_CHANGE_INSERTs for a single xl_heap_multi_insert record. To solve the problem add a clear_toast_afterwards boolean to ReorderBufferChange's union member that's used by modifications. All row changes but multi_inserts always set that to true, but multi_insert sets it only for the last change generated. Add a regression test covering decoding of multi_inserts - there was none at all before. Backpatch to 9.4 where logical decoding was introduced. Bug found by Petr Jelinek.	11 years ago
Robert Haas	b89e151054	Introduce logical decoding. ... This feature, building on previous commits, allows the write-ahead log stream to be decoded into a series of logical changes; that is, inserts, updates, and deletes and the transactions which contain them. It is capable of handling decoding even across changes to the schema of the effected tables. The output format is controlled by a so-called "output plugin"; an example is included. To make use of this in a real replication system, the output plugin will need to be modified to produce output in the format appropriate to that system, and to perform filtering. Currently, information can be extracted from the logical decoding system only via SQL; future commits will add the ability to stream changes via walsender. Andres Freund, with review and other contributions from many other people, including Álvaro Herrera, Abhijit Menon-Sen, Peter Gheogegan, Kevin Grittner, Robert Haas, Heikki Linnakangas, Fujii Masao, Abhijit Menon-Sen, Michael Paquier, Simon Riggs, Craig Ringer, and Steve Singer.	12 years ago