From e4d2fae2907bd986a90b547cf02f0a3c51e6cbf5 Mon Sep 17 00:00:00 2001 From: Emre Hasegeli Date: Mon, 20 Mar 2023 17:02:45 +0100 Subject: [PATCH v16] doc: Clarify pgoutput options Author: Emre Hasegeli Reviewed-by: Peter Smith Reviewed-by: Amit Kapila Backpatch-through: 12 Discussion: https://www.postgresql.org/message-id/flat/CAE2gYzwdwtUbs-tPSV-QBwgTubiyGD2ZGsSnAVsDfAGGLDrGOA%40mail.gmail.com --- doc/src/sgml/logical-replication.sgml | 5 +- doc/src/sgml/protocol.sgml | 85 +++++++++++++++++++++++++-- 2 files changed, 84 insertions(+), 6 deletions(-) diff --git a/doc/src/sgml/logical-replication.sgml b/doc/src/sgml/logical-replication.sgml index c2a749d882..ca852c5506 100644 --- a/doc/src/sgml/logical-replication.sgml +++ b/doc/src/sgml/logical-replication.sgml @@ -525,21 +525,21 @@ test_sub=# SELECT * FROM t3; Examples: Deferred Replication Slot Creation There are some cases (e.g. ) where, if the remote replication slot was not created automatically, the user must create it manually before the subscription can be activated. The steps to create the slot and activate the subscription are shown in the following examples. - These examples specify the standard logical decoding plugin + These examples specify the standard logical decoding output plugin (pgoutput), which is what the built-in logical replication uses. First, create a publication for the examples to use. test_pub=# CREATE PUBLICATION pub1 FOR ALL TABLES; CREATE PUBLICATION @@ -1636,21 +1636,22 @@ CONTEXT: processing remote data for replication origin "pg_16395" during "INSER transactional consistency is guaranteed for the publications within any single subscription. Logical replication is built with an architecture similar to physical streaming replication (see ). It is implemented by walsender and apply processes. The walsender process starts logical decoding (described in ) of the WAL and loads the standard - logical decoding plugin (pgoutput). The plugin transforms the changes read + logical decoding output plugin (pgoutput). The plugin + transforms the changes read from WAL to the logical replication protocol (see ) and filters the data according to the publication specification. The data is then continuously transferred using the streaming replication protocol to the apply worker, which maps the data to local tables and applies the individual changes as they are received, in correct transactional order. The apply process on the subscriber database always runs with diff --git a/doc/src/sgml/protocol.sgml b/doc/src/sgml/protocol.sgml index b11d9a6ba3..5dff07110d 100644 --- a/doc/src/sgml/protocol.sgml +++ b/doc/src/sgml/protocol.sgml @@ -2534,21 +2534,24 @@ psql "dbname=postgres replication=database" -c "IDENTIFY_SYSTEM;" The WAL location to begin streaming at. option_name - The name of an option passed to the slot's logical decoding plugin. + The name of an option passed to the slot's logical decoding output + plugin. See for + options that are accepted by the standard (pgoutput) + plugin. option_value Optional value, in the form of a string constant, associated with the specified option. @@ -3071,36 +3074,43 @@ psql "dbname=postgres replication=database" -c "IDENTIFY_SYSTEM;" flow started by the START_REPLICATION SLOT slot_name LOGICAL replication command. The logical streaming replication protocol builds on the primitives of the physical streaming replication protocol. + + PostgreSQL logical decoding supports output + plugins. pgoutput is the standard one used for + the built-in logical replication. + + Logical Streaming Replication Parameters - The logical replication START_REPLICATION command - accepts following parameters: + Using the START_REPLICATION command, + pgoutput accepts the following options: proto_version Protocol version. Currently versions 1, 2, - 3, and 4 are supported. + 3, and 4 are supported. A valid + version is required. Version 2 is supported only for server version 14 and above, and it allows streaming of large in-progress transactions. Version 3 is supported only for server version 15 and above, and it allows streaming of two-phase commits. @@ -3113,20 +3123,87 @@ psql "dbname=postgres replication=database" -c "IDENTIFY_SYSTEM;" publication_names Comma separated list of publication names for which to subscribe (receive changes). The individual publication names are treated as standard objects names and can be quoted the same as needed. + At least one publication name is required. + + + + + + + binary + + + + Boolean option to use binary transfer mode. Binary mode is faster + than the text mode but slightly less robust. + + + + + + + messages + + + + Boolean option to enable sending the messages that are written + by pg_logical_emit_message. + + + + + + + streaming + + + + Boolean option to enable streaming of in-progress transactions. + It accepts an additional value "parallel" to enable sending extra + information with some messages to be used for parallelisation. + Minimum protocol version 2 is required to turn it on. Minimum protocol + version 4 is required for the "parallel" option. + + + + + + + two_phase + + + + Boolean option to enable two-phase transactions. Minimum protocol + version 3 is required to turn it on. + + + + + + + origin + + + + Option to send changes by their origin. Possible values are "none" + to only send the changes that have no origin associated, or "any" + to send the changes regardless of their origin. This can be used + to avoid loops (infinite replication of the same data) among + replication nodes. Logical Replication Protocol Messages -- 2.39.3 (Apple Git-145)