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Accept InsertMessage with zero-column tuples - #86
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PostgreSQL emits zero-column tuples for inserts into tables with no replicated columns: tables created with no columns, tables whose columns have all been dropped, and (before PG 18) tables with only generated columns. The payload is then 7 bytes (relation ID, 'N', column count 0), but InsertMessage.Decode required at least 8, so decoding failed with "InsertMessage must have 8 bytes, got 7 bytes" and a replication stream could not progress past such a change. The in-stream InsertMessageV2 check had the same off-by-one (12 instead of 11).
ilidemi
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Oct 9, 2026
Include jackc/pglogrepl#86 to support zero-column inserts
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PostgreSQL can have tables with no replicated columns: created that way initially, columns dropped later, or only generated columns. InsertMessage payload for those is 7 bytes long (4-byte relation ID, 'N', 2-byte column count of 0), but InsertMessage.Decode fails with
InsertMessage must have 8 bytes, got 7 bytes.This is an arguably questionable case to try and replicate, however there can be a situation where a publication is created for all tables, only a few are actually being consumed in CDC/replication downstream, then an unrelated table creation/modification breaks a running pipeline without a way to recover. UpdateMessage and DeleteMessage already support zero-column tuples.
InsertMessageV2 check had the same off-by-one (12 instead of 11), also fixed here. Added tests for both cases.