ClickHouse/docs/en/interfaces/tcp.md

slug	sidebar_position	sidebar_label
/en/interfaces/tcp	18	Native Interface (TCP)

Native Interface (TCP)

The native protocol is used in the command-line client, for inter-server communication during distributed query processing, and also in other C++ programs. Unfortunately, native ClickHouse protocol does not have formal specification yet, but it can be reverse-engineered from ClickHouse source code (starting around here) and/or by intercepting and analyzing TCP traffic.

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