nameexhaustion opened a new issue, #2246: URL: https://github.com/apache/iceberg-python/issues/2246
### Apache Iceberg version None ### Please describe the bug 🐞 ### Reproducible example ```python from __future__ import annotations import itertools from datetime import datetime from functools import partial import pyarrow as pa from pyiceberg.catalog.sql import SqlCatalog from pyiceberg.schema import Schema as IcebergSchema from pyiceberg.types import ( IntegerType, ListType, NestedField, StringType, StructType, TimestampType, ) import polars as pl tmp_path = ".env/_tmp" catalog = SqlCatalog( "default", uri="sqlite:///:memory:", warehouse=f"file://{tmp_path}", ) catalog.create_namespace("namespace") next_field_id = partial(next, itertools.count()) catalog.create_table( "namespace.table", IcebergSchema( NestedField( field_id=next_field_id(), name="column_1", field_type=ListType( element_id=next_field_id(), element=StructType( NestedField( field_id=next_field_id(), name="field_1", field_type=ListType( element_id=next_field_id(), element=StructType( NestedField(field_id=next_field_id(), name="key", field_type=ListType( element_id=next_field_id(), element=TimestampType(), element_required=False, ), required=True), NestedField(field_id=next_field_id(), name="value", field_type=ListType( element_id=next_field_id(), element=IntegerType(), element_required=False, ), required=False), ), element_required=False ), required=False, ), NestedField(field_id=next_field_id(), name="field_2", field_type=IntegerType(), required=False), NestedField(field_id=next_field_id(), name="field_3", field_type=StringType(), required=False), ), element_required=False, ), required=False, ), ), ) # fmt: skip tbl = catalog.load_table("namespace.table") df_dict = { "column_1": [ [ { "field_1": [ {"key": [datetime(2025, 1, 1), None], "value": [1, 2, None]} ], "field_2": 7, "field_3": "F3", } ], [ { "field_1": [{"key": [datetime(2025, 1, 1), None], "value": None}], "field_2": 7, "field_3": "F3", } ], [{"field_1": None, "field_2": None, "field_3": None}], [None], None, ], } arrow_tbl = pa.Table.from_pydict( df_dict, schema=pa.schema( [ ( "column_1", pa.large_list( pa.struct( [ ( "field_1", pa.large_list( pa.struct( [ pa.field( "key", pa.large_list(pa.timestamp("us")), nullable=False, ), ("value", pa.large_list(pa.int32())), ] ) ), ), ("field_2", pa.int32()), ("field_3", pa.string()), ] ) ), ) ] ), ) tbl.append(arrow_tbl) arrow_tbl_from_scan = tbl.scan().to_arrow() assert arrow_tbl.equals(arrow_tbl) # OK # Fails: # assert arrow_tbl.equals(arrow_tbl_from_scan) print( pl.concat( [ pl.DataFrame(arrow_tbl).rename({"column_1": "column_1_expected"}), pl.DataFrame(arrow_tbl_from_scan).rename({"column_1": "column_1_actual"}), ], how="horizontal", ).with_columns( matching=pl.col("column_1_expected").eq_missing(pl.col("column_1_actual")) ) ) # shape: (5, 3) # ┌─────────────────────────────────┬─────────────────────────────────┬──────────┐ # │ column_1_expected ┆ column_1_actual ┆ matching │ # │ --- ┆ --- ┆ --- │ # │ list[struct[3]] ┆ list[struct[3]] ┆ bool │ # ╞═════════════════════════════════╪═════════════════════════════════╪══════════╡ # │ [{[{[2025-01-01 00:00:00, null… ┆ [{[{[2025-01-01 00:00:00, null… ┆ true │ # │ [{[{[2025-01-01 00:00:00, null… ┆ [{[{[2025-01-01 00:00:00, null… ┆ true │ # │ [{null,null,null}] ┆ [{[],null,null}] ┆ false │ # │ [null] ┆ [null] ┆ true │ # │ null ┆ [] ┆ false │ # └─────────────────────────────────┴─────────────────────────────────┴──────────┘ ``` ### Issue description Outer NULLs become empty lists inside the Parquet file written by PyIceberg. Note that the reproducible example uses `tbl.append(<arrow table>)`, but this will affect `pl.DataFrame.write_iceberg(..)` in the same way. ### Expected behavior `column_1_actual == column_1_expected` for all rows in the example. ### Willingness to contribute - [ ] I can contribute a fix for this bug independently - [ ] I would be willing to contribute a fix for this bug with guidance from the Iceberg community - [ ] I cannot contribute a fix for this bug at this time -- 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.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