postgresql/contrib/test_decoding/sql/truncate.sql

-- predictability
SET synchronous_commit = on;

SELECT 'init' FROM pg_create_logical_replication_slot('regression_slot', 'test_decoding');

CREATE TABLE tab1 (id serial unique, data int);
CREATE TABLE tab2 (a int primary key, b int);

TRUNCATE tab1;
TRUNCATE tab1, tab1 RESTART IDENTITY CASCADE;
TRUNCATE tab1, tab2;

SELECT data FROM pg_logical_slot_get_changes('regression_slot', NULL, NULL, 'include-xids', '0', 'skip-empty-xacts', '1');
SELECT pg_drop_replication_slot('regression_slot');
Force synchronous commit to be enabled for all test_decoding tests. Without that the tests fail when forced to be run against a cluster with synchronous_commit = off (as the WAL might not yet be flushed to disk by the point logical decoding gets called, and thus the expected output breaks). Most tests already do that, add it to a few newer tests. Author: Andres Freund 2018-10-10 16:53:02 -04:00			`-- predictability`
			`SET synchronous_commit = on;`

Logical decoding of TRUNCATE Add a new WAL record type for TRUNCATE, which is only used when wal_level >= logical. (For physical replication, TRUNCATE is already replicated via SMGR records.) Add new callback for logical decoding output plugins to receive TRUNCATE actions. Author: Simon Riggs <simon@2ndquadrant.com> Author: Marco Nenciarini <marco.nenciarini@2ndquadrant.it> Author: Peter Eisentraut <peter.eisentraut@2ndquadrant.com> Reviewed-by: Petr Jelinek <petr.jelinek@2ndquadrant.com> Reviewed-by: Andres Freund <andres@anarazel.de> Reviewed-by: Alvaro Herrera <alvherre@alvh.no-ip.org> 2018-04-07 11:17:56 -04:00			`SELECT 'init' FROM pg_create_logical_replication_slot('regression_slot', 'test_decoding');`

			`CREATE TABLE tab1 (id serial unique, data int);`
			`CREATE TABLE tab2 (a int primary key, b int);`

			`TRUNCATE tab1;`
			`TRUNCATE tab1, tab1 RESTART IDENTITY CASCADE;`
			`TRUNCATE tab1, tab2;`

			`SELECT data FROM pg_logical_slot_get_changes('regression_slot', NULL, NULL, 'include-xids', '0', 'skip-empty-xacts', '1');`
Implement streaming mode in ReorderBuffer. Instead of serializing the transaction to disk after reaching the logical_decoding_work_mem limit in memory, we consume the changes we have in memory and invoke stream API methods added by commit 45fdc9738b. However, sometimes if we have incomplete toast or speculative insert we spill to the disk because we can't generate the complete tuple and stream. And, as soon as we get the complete tuple we stream the transaction including the serialized changes. We can do this incremental processing thanks to having assignments (associating subxact with toplevel xacts) in WAL right away, and thanks to logging the invalidation messages at each command end. These features are added by commits 0bead9af48 and c55040ccd0 respectively. Now that we can stream in-progress transactions, the concurrent aborts may cause failures when the output plugin consults catalogs (both system and user-defined). We handle such failures by returning ERRCODE_TRANSACTION_ROLLBACK sqlerrcode from system table scan APIs to the backend or WALSender decoding a specific uncommitted transaction. The decoding logic on the receipt of such a sqlerrcode aborts the decoding of the current transaction and continue with the decoding of other transactions. We have ReorderBufferTXN pointer in each ReorderBufferChange by which we know which xact it belongs to. The output plugin can use this to decide which changes to discard in case of stream_abort_cb (e.g. when a subxact gets discarded). We also provide a new option via SQL APIs to fetch the changes being streamed. Author: Dilip Kumar, Tomas Vondra, Amit Kapila, Nikhil Sontakke Reviewed-by: Amit Kapila, Kuntal Ghosh, Ajin Cherian Tested-by: Neha Sharma, Mahendra Singh Thalor and Ajin Cherian Discussion: https://postgr.es/m/688b0b7f-2f6c-d827-c27b-216a8e3ea700@2ndquadrant.com 2020-08-07 22:04:39 -04:00			`SELECT pg_drop_replication_slot('regression_slot');`