Function fields_semantically_equal 

fn fields_semantically_equal(
    expected_field: &Field,
    actual_field: &Field,
) -> bool

Returns true when two fields describe the same column semantics: same name, same data type, and same nullability.

Arrow Field metadata is auxiliary information (indexing, encoding, compression hints, …) and does not participate in the comparison. This applies to every field, JSON columns included: JSON identity keys (greptime:type, ARROW:extension:metadata) are never compared here. The wire/decoded physical-type difference of JSON columns is exempted separately by json_fields_compatible.