lyne7-sc opened a new issue, #3475:
URL: https://github.com/apache/iceberg-rust/issues/3475

   ### Apache Iceberg Rust version
   
   main(acd610997de7)
   
   ### Describe the bug
   
   Reading older Parquet files after a column rename can silently return values 
under the wrong columns when the projection order differs from the file order 
and the corresponding column types and nullability match.
   
   For example, an orders table contains `paid_amount` and `refund_amount`, 
both nullable DECIMAL(18, 2). After renaming `paid_amount` to `payment_amount`, 
requesting `[refund_amount, payment_amount]` can return the payment amount as 
the refund amount and vice versa.
   
   The Parquet reader returns selected columns in file order. 
`RecordBatchTransformer` can mistake the required reordering for a name-only 
change because its schema comparison does not check field IDs.
   
   
   ### To Reproduce
   
   1. Write a Parquet file with these fields in physical order:
      - `paid_amount`: field ID 1, nullable DECIMAL(18, 2), value `100.00`.
      - `refund_amount`: field ID 2, nullable DECIMAL(18, 2), value `20.00`.
   2. Construct an Iceberg scan schema with `payment_amount` (ID 1) and 
`refund_amount` (ID 2), preserving their types and nullability. Leave the 
Parquet file unchanged.
   3. Pass this schema to `FileScanTask` via `.with_schema(...)`, set 
`.with_project_field_ids(vec![2, 1])`, and read through `ArrowReader`.
   
   The output columns are `[refund_amount, payment_amount]`, but the values 
remain `[100.00, 20.00]`.
   
   
   ### Expected behavior
   
   The output values should follow the requested field IDs regardless of column 
renames or physical column order.
   
   ### Willingness to contribute
   
   I can contribute a fix for this bug independently


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