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kernel/src/engine/arrow_utils.rs

@@ -558,6 +558,10 @@ fn get_indices(
                     }
                 }
                 _ => {
+                    // we don't care about matching on nullability or metadata here so pass `false`
+                    // as the final argument. These can differ between the delta schema and the
+                    // parquet schema without causing issues in reading the data. We fix them up in
+                    // expression evaluation later.
                     match ensure_data_types(&requested_field.data_type, field.data_type(), false)? {
                         DataTypeCompat::Identical => {
                             reorder_indices.push(ReorderIndex::identity(index))