Considerations and limitations for maintenance jobs

Compaction is only supported on Apache Parquet file types.

Compaction doesn’t support data type: Fixed.

Compaction doesn’t support compression types: brotli, lz4.

Snapshots will be preserved only when both criteria are satisfied: the minimum number of snapshots to keep and the specified retention period.

Snapshot management deletes expired snapshot metadata from Apache Iceberg, preventing time travel queries for expired snapshots and optionally deleting associated data files.

Snapshot management does not support retention values you configure as Iceberg table properties in the metadata.json file or through an ALTER TABLE SET TBLPROPERTIES SQL command, including branch or tag-based retention. Snapshot management is disabled when you configure a branch or tag-based retention policy, or configure a retention policy on the metadata.json file that is longer than the values configured through the PutTableMaintenanceConfiguration API. In these cases S3 will not expire or remove snapshots and you will need to manually delete snapshots or remove the properties from your Iceberg table to avoid storage charges.

Unreferenced file removal deletes data and metadata files that are no longer referenced by Iceberg metadata if their creation time is before the retention period.