Fix/field ordering bug #8
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Add regression test that demonstrates the field ordering bug where cast_table_safe fails when source table fields are in a different order than the target schema, even when all field names and types match.
Reorder source table columns to match target schema order before casting. PyArrow's cast() matches fields by position, not name, so tables with different field ordering would fail even when all field names and types matched.
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Hi Nico, I think I found a bug while using this package.
Problem
When loading JSON data (where field order isn't guaranteed), subsequent loads could fail with:
This occurs because PyArrow's
table.cast()matches fields by position, not by name. Fails even though all field names and types match.Solution
Reorder source table columns to match target schema order before casting
Changes
tests/test_schema_casting.py: Add test for field orderingsrc/dlt_iceberg/schema_casting.py: Add column reordering beforetable.cast()incast_table_safe()