v.24.1Improvement

Added Comments to System Table Columns for Clarity and Documentation Improvement

Official CH changelog text
Added comments (brief descriptions) to all columns of system tables. There are several reasons for this: - We use system tables a lot, and sometimes it could be very difficult for developer to understand the purpose and the meaning of a particular column. - We change (add new ones or modify existing) system tables a lot and the documentation for them is always outdated. For example take a look at the documentation page for system.parts. It misses a lot of columns - We would like to eventually generate documentation directly from ClickHouse. #58356 (Nikita Mikhaylov).
Added descriptive comments to all columns of ClickHouse system tables to clarify their purpose and meaning.

Why it matters

System tables in ClickHouse are extensively used but often difficult for developers to fully understand due to lack of clear column descriptions. Documentation for these tables frequently becomes outdated as columns are added or modified. This feature aims to provide inline, accurate descriptions within the system tables themselves, improving usability and paving the way for automatic documentation generation directly from ClickHouse.

How to use it

Users can view the added comments directly by querying the system tables' metadata or looking at their schema descriptions. The comments are embedded in the system tables' column definitions and require no additional configuration to access.

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