[ https://issues.apache.org/jira/browse/ARROW-13151?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17374935#comment-17374935 ]
Micah Kornfield commented on ARROW-13151: ----------------------------------------- {quote}As a side-note, if you do change the ugly "list.item" access {quote} Yeah this would be a seperate change, and I think we could make it be backwards compatible. This would be a separate issue. The reason why removing list.item makes sense is that there are legacy encodings that encode lists in different ways, it would be nice to have a uniform access to these different types (i.e. schema evolution), I'll open up a separate item to track this and we can have more discussion there, I don't expect anyone would take this up any time soon. > [Python] Unable to read single child field of struct column from Parquet > ------------------------------------------------------------------------ > > Key: ARROW-13151 > URL: https://issues.apache.org/jira/browse/ARROW-13151 > Project: Apache Arrow > Issue Type: Bug > Components: Parquet, Python > Reporter: Angus Hollands > Priority: Major > > Given the following table > {code:java} > data = {"root": [[{"addr": {"this": 3, "that": 3}}]]} > table = pa.Table.from_pydict(data) > {code} > reading the nested column leads to an {{pyarrow.lib.ArrowInvalid}} error: > {code:java} > pq.write_table(table, "/tmp/table.parquet") > file = pq.ParquetFile("/tmp/table.parquet") > array = file.read(["root.list.item.addr.that"]) > {code} > Traceback: > {code:java} > Traceback (most recent call last): > File "....", line 21, in <module> > array = file.read(["root.list.item.addr.that"]) > File > "/home/angus/.mambaforge/envs/awkward/lib/python3.9/site-packages/pyarrow/parquet.py", > line 383, in read > return self.reader.read_all(column_indices=column_indices, > File "pyarrow/_parquet.pyx", line 1097, in > pyarrow._parquet.ParquetReader.read_all > File "pyarrow/error.pxi", line 97, in pyarrow.lib.check_status > pyarrow.lib.ArrowInvalid: List child array invalid: Invalid: Struct child > array #0 does not match type field: struct<that: int64> vs struct<that: > int64, this: int64> > {code} > It's possible that I don't quite understand this properly - am I doing > something wrong? -- This message was sent by Atlassian Jira (v8.3.4#803005)