v.23.10Improvement

Improved MySQL Compatibility: New Fields in Information Schema Tables and Columns

To improve compatibility with MySQL, 1. information_schema.tables now includes the new field table_rows, and 2. information_schema.columns now includes the new field extra. #55215 (Robert Schulze).
ClickHouse's information_schema.tables now includes the new field table_rows, and information_schema.columns includes the new field extra for improved MySQL compatibility.

Why it matters

This feature addresses the need for enhanced compatibility with MySQL by extending the information_schema tables. Adding table_rows to information_schema.tables provides users with the approximate row count per table, while the extra field in information_schema.columns offers additional column metadata. This helps users and tools that rely on MySQL-compatible metadata to function better with ClickHouse.

How to use it

Users can query the new fields table_rows from information_schema.tables and extra from information_schema.columns as part of their standard metadata queries, enabling better introspection and MySQL-compatible schema discovery without any additional configuration.