gabeiglio commented on code in PR #1443: URL: https://github.com/apache/iceberg-python/pull/1443#discussion_r1912344028
########## pyiceberg/io/pyarrow.py: ########## @@ -1216,6 +1216,25 @@ def _field_id(self, field: pa.Field) -> int: return -1 +def _get_column_projection_values( + file: DataFile, + projected_schema: Schema, + projected_field_ids: Set[int], + file_project_schema: Schema, + partition_spec: Optional[PartitionSpec] = None, +) -> Dict[str, object]: + """Apply Column Projection rules to File Schema.""" + projected_missing_fields = {} + + for field_id in projected_field_ids.difference(file_project_schema.field_ids): + if partition_spec is not None: + for partition_field in partition_spec.fields_by_source_id(field_id): + if isinstance(partition_field.transform, IdentityTransform) and partition_field.name in file.partition.__dict__: + projected_missing_fields[partition_field.name] = file.partition.__dict__[partition_field.name] Review Comment: Oh! thanks for the context! I think positions accessors - since it traverses the table schema - cannot access partitions fields, therefore if a column has two or more partition the method wont see them. One question I have its that if the file.partition metadata is written in order then it is guaranteed that the first record in the tuple would be the first partition column from the partition spec? -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: issues-unsubscr...@iceberg.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org --------------------------------------------------------------------- To unsubscribe, e-mail: issues-unsubscr...@iceberg.apache.org For additional commands, e-mail: issues-h...@iceberg.apache.org