Arrow recently introduced FixedShapeTensor and VariableShapeTensor canonical extension types that use FixedSizeList and StructArray(List, FixedSizeList) as storage respectfully. These are targeted at machine learning and scientific applications that deal with large datasets and would benefit from using Parquet as on disk storage.
However currently FixedSizeList is stored as List in Parquet which adds significant conversion overhead when reading and writing as discussed here. It would therefore be beneficial to introduce a FIXED_SIZE_LIST logical type to Parquet.
Replicated from mailing list
Arrow recently introduced FixedShapeTensor and VariableShapeTensor canonical extension types that use FixedSizeList and StructArray(List, FixedSizeList) as storage respectfully. These are targeted at machine learning and scientific applications that deal with large datasets and would benefit from using Parquet as on disk storage.
However currently FixedSizeList is stored as List in Parquet which adds significant conversion overhead when reading and writing as discussed here. It would therefore be beneficial to introduce a FIXED_SIZE_LIST logical type to Parquet.
Reporter: Rok Mihevc
PRs and other links:
Note: This issue was originally created as PARQUET-2474. Please see the migration documentation for further details.