Disable Table Functions in Readonly Mode for Inserts

Why it matters

This feature prevents the execution of table functions in INSERT statements if ClickHouse is running in readonly mode, ensuring data safety by avoiding unintended modifications during read-only operation periods.

How to use it

When ClickHouse is set to readonly mode (e.g., via the readonly setting), any INSERT statements that use table functions will be disabled automatically. Users do not need to make any manual changes; the restriction is enforced internally.