v.21.7Improvement

Handle Column Name Clashes for Join Table Engine

Handle column name clashes for Join table engine. Closes #20309. #23769 (Vladimir).
Handle column name clashes for the Join table engine to avoid conflicts during join operations.

Why it matters

This feature addresses the issue of column name clashes when using the Join table engine, ensuring that columns from joined tables do not conflict or cause ambiguous references. It improves stability and correctness of queries involving joins.

How to use it

The feature is applied automatically in the Join table engine without requiring additional user configuration. Users benefit from reliable join results even when source tables have overlapping column names.