pgoutput

说明

本节介绍逻辑复制协议，它是一种以复制命令 START_REPLICATION SLOT slot_name LOGICAL 开始的消息流。 逻辑流复制协议构建在物理流复制协议的基本机制之上。 PostgreSQL 的逻辑解码支持输出插件。 pgoutput 是内置逻辑复制使用的标准插件。

接口类别

逻辑解码输出插件

处理函数或例程

_PG_output_plugin_init

记录的回调

20

LOGICALREP_PROTO_MIN_VERSION_NUM

1

LOGICALREP_PROTO_VERSION_NUM

1

LOGICALREP_PROTO_STREAM_VERSION_NUM

2

LOGICALREP_PROTO_TWOPHASE_VERSION_NUM

3

LOGICALREP_PROTO_STREAM_PARALLEL_VERSION_NUM

4

接口与能力边界

矩阵记录此源码构建实际注册的回调。注册表明实现了相应接口钩子；操作是否允许还取决于选项、查询形式、权限和提供方规则。

下方保留同版本完整手册，包括配置、约束和示例。不声称已进行运行时能力测试。

输出与协议边界

回调是否存在、协议版本、客户端协商及已启用的插件选项分别记录。流式处理和两阶段处理需要匹配的协议与配置。

test_decoding 是示例／测试输出格式，pgoutput 实现逻辑复制协议，两者的输出约定不可互换。

核心源码中注册的实现

{
	cb->startup_cb = pgoutput_startup;
	cb->begin_cb = pgoutput_begin_txn;
	cb->change_cb = pgoutput_change;
	cb->truncate_cb = pgoutput_truncate;
	cb->message_cb = pgoutput_message;
	cb->commit_cb = pgoutput_commit_txn;

	cb->begin_prepare_cb = pgoutput_begin_prepare_txn;
	cb->prepare_cb = pgoutput_prepare_txn;
	cb->commit_prepared_cb = pgoutput_commit_prepared_txn;
	cb->rollback_prepared_cb = pgoutput_rollback_prepared_txn;
	cb->filter_by_origin_cb = pgoutput_origin_filter;
	cb->shutdown_cb = pgoutput_shutdown;

	/* transaction streaming */
	cb->stream_start_cb = pgoutput_stream_start;
	cb->stream_stop_cb = pgoutput_stream_stop;
	cb->stream_abort_cb = pgoutput_stream_abort;
	cb->stream_commit_cb = pgoutput_stream_commit;
	cb->stream_change_cb = pgoutput_change;
	cb->stream_message_cb = pgoutput_message;
	cb->stream_truncate_cb = pgoutput_truncate;
	/* transaction streaming - two-phase commit */
	cb->stream_prepare_cb = pgoutput_stream_prepare_txn;
}

相关条目

• 逻辑解码输出接口
• 既有扩展目录标识
• 逻辑复制 Begin 消息
• 逻辑复制 Relation 消息
• 逻辑元组表示
• 逻辑复制 Stream Start 消息
• 逻辑复制 Prepare 消息

文档与源码

• PostgreSQL 18 English manual
• src/backend/replication/pgoutput/pgoutput.c:262
• PostgreSQL 18 English manual
• Logical replication protocol constants

版本比较

PostgreSQL 17 → 18: 属性变化。

以下差异保留原始字段名与英文源描述。

--- PostgreSQL 17
+++ PostgreSQL 18
@@ -27,7 +27,7 @@
       "name": "proto_version"
     },
     {
-      "definition": "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.",
+      "definition": "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.",
       "name": "publication_names"
     },
     {
@@ -47,7 +47,7 @@
       "name": "two_phase"
     },
     {
-      "definition": "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.",
+      "definition": "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.",
       "name": "origin"
     }
   ],

比较已记录的接口与属性，排除来源指纹和构建元数据。某个样本中没有记录，不能据此判断实际引入或移除的版本。