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Function Name Normalization for ALTER Queries to Prevent Metadata Mismatches

Official CH changelog text
Function name normalization for ALTER queries. This helps avoid metadata mismatch between creating table with indices/projections and adding indices/projections via alter commands. This is a follow-up PR of https://github.com/ClickHouse/ClickHouse/pull/20174. Mark as improvements as there are no bug reports and the senario is somehow rare. #31095 (Amos Bird).
Introduces function name normalization for ALTER queries to ensure consistency between table metadata when creating tables with indices or projections and when adding them later via ALTER commands.

Why it matters

This feature addresses potential metadata mismatches caused by differences in function name representations between table creation and subsequent ALTER commands. By normalizing function names, it improves metadata consistency, reducing unexpected issues when adding indices or projections through ALTER queries.

How to use it

Users benefit from this feature automatically when using ALTER queries to add indices or projections. No additional configuration or syntax changes are required—the normalization is applied internally during processing of ALTER commands.

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