Error2 reports

Fix `ColumnNotFoundError`

in Polars

✅ Solution

This error typically occurs in polars. Check the example issues for common solutions.

Related Issues

Real GitHub issues where developers encountered this error:

LazyFrame: ColumnNotFoundError when .with_columns() reassigns an existing column and adds a new expression before .group_by().agg()Jun 10, 2026

Added column on LazyFrame throws `ColumnNotFound` even though it appears to existJun 9, 2026

Timeline

First reported:Jun 9, 2026

Last reported:Jun 10, 2026

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