v.21.1Improvements

Check System Log Tables' Engine Definition Grammar to Prevent Configuration Errors

Check system log tables' engine definition grammar to prevent some configuration errors. Notes that this grammar check is not semantical, that means such mistakes as non-existent columns / expression functions would be not found out util the table is created. #17739 (Du Chuan).
Added syntax validation for the engine definition grammar of system log tables to prevent configuration errors.

Why it matters

This feature aims to catch configuration mistakes in system log table engine definitions early by performing grammar checks. It helps users avoid invalid engine settings before table creation, improving reliability and reducing runtime errors. Note that this check is purely syntactical and does not verify semantic correctness such as the existence of columns or functions.

How to use it

Users benefit from this feature automatically when defining system log tables. When specifying the engine for a system log table, ClickHouse will validate the syntax of the engine definition and report grammar errors before creating the table.