{"Entry":{"collection":"protocol","key":"logical-begin","name":"Begin (logical replication)","aliases":["Begin"],"metadata":{"aliases":["Begin"],"category":"Logical replication formats","content_hash":"a290f5e8d06c7c3fb892255df43d86eb48c7cdc34e7318965cebbe588f87689d","imported_at":"2026-09-30T00:40:44.603465+08:00","name":"Begin (logical replication)","name_zh":"","slug":"logical-begin","summary":"Logical replication Begin format. Identifies the message as a begin message."}},"Definition":{"Collection":"protocol","Key":"logical-begin","SourceDatabase":"center","Version":"18","SourceTable":"protocol_message","SourceKey":"logical-begin","SourceRevision":"555610c24d53e4316da5b7d3fc25c279d96856d5e0e23ee308c328c5fa881d9f","Facts":{"comparison_data":{"fields":[{"description":"Identifies the message as a begin message.","format":"Byte1('B')"},{"description":"The final LSN of the transaction.","format":"Int64 (XLogRecPtr)"},{"description":"Commit timestamp of the transaction. 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Identifies the message as a begin message.","BodyHTML":"\u003cdl\u003e\u003cdd\u003e\n\u003cdiv\u003e\n\u003cdl\u003e\n\u003cdt\u003e\u003cspan\u003eByte1(\u0026#39;B\u0026#39;)\u003c/span\u003e\u003c/dt\u003e\n\u003cdd\u003e\n\u003cp\u003eIdentifies the message as a begin message.\u003c/p\u003e\n\u003c/dd\u003e\n\u003cdt\u003e\u003cspan\u003eInt64 (XLogRecPtr)\u003c/span\u003e\u003c/dt\u003e\n\u003cdd\u003e\n\u003cp\u003eThe final LSN of the transaction.\u003c/p\u003e\n\u003c/dd\u003e\n\u003cdt\u003e\u003cspan\u003eInt64 (TimestampTz)\u003c/span\u003e\u003c/dt\u003e\n\u003cdd\u003e\n\u003cp\u003eCommit timestamp of the transaction. 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Identifies the message as a begin message."],"manual_html":"\u003cdl\u003e\u003cdd\u003e\n\u003cdiv class=\"variablelist\"\u003e\n\u003cdl class=\"variablelist\"\u003e\n\u003cdt\u003e\u003cspan class=\"term\"\u003eByte1('B')\u003c/span\u003e\u003c/dt\u003e\n\u003cdd\u003e\n\u003cp\u003eIdentifies the message as a begin message.\u003c/p\u003e\n\u003c/dd\u003e\n\u003cdt\u003e\u003cspan class=\"term\"\u003eInt64 (XLogRecPtr)\u003c/span\u003e\u003c/dt\u003e\n\u003cdd\u003e\n\u003cp\u003eThe final LSN of the transaction.\u003c/p\u003e\n\u003c/dd\u003e\n\u003cdt\u003e\u003cspan class=\"term\"\u003eInt64 (TimestampTz)\u003c/span\u003e\u003c/dt\u003e\n\u003cdd\u003e\n\u003cp\u003eCommit timestamp of the transaction. 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The following messages (Stream Start, Stream Stop, Stream Commit, and Stream Abort) are available since protocol version 2. The following messages (Begin Prepare, Prepare, Commit Prepared, Rollback Prepared, Stream Prepare) are available since protocol version 3. The following message parts are shared by the above messages."],"title":"Protocol context"}],"tables":[{"columns":[{"key":"c0","label":"Position"},{"key":"c1","label":"Format"},{"key":"c2","label":"Meaning"}],"key":"fields","rows":[{"c0":"1","c1":"Byte1('B')","c2":"Identifies the message as a begin message."},{"c0":"2","c1":"Int64 (XLogRecPtr)","c2":"The final LSN of the transaction."},{"c0":"3","c1":"Int64 (TimestampTz)","c2":"Commit timestamp of the transaction. 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