> For the complete documentation index, see [llms.txt](https://docs.postgresql.tw/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.postgresql.tw/13/server-programming/logical-decoding/logical-decoding-sql-interface.md).

# 48.4. Logical Decoding SQL Interface

See [Section 9.27.6](https://www.postgresql.org/docs/13/functions-admin.html#FUNCTIONS-REPLICATION) for detailed documentation on the SQL-level API for interacting with logical decoding.

Synchronous replication (see [Section 26.2.8](https://www.postgresql.org/docs/13/warm-standby.html#SYNCHRONOUS-REPLICATION)) is only supported on replication slots used over the streaming replication interface. The function interface and additional, non-core interfaces do not support synchronous replication.


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