IcebergCompatV3

This protocol change introduces a compatibility flag, which ensures that a delta table can be safely read and written as an Apache Iceberg™ format table, similar to IcebergCompatV1 and IcebergCompatV2.

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IcebergCompatV3

New Section after Iceberg Compatibility V2

Iceberg Compatibility V3

This table feature (icebergCompatV3) ensures that Delta tables can be converted to Apache Iceberg™ format, though this table feature does not implement or specify that conversion.

To support this feature:

• Since this table feature depends on Column Mapping, the table must be on Reader Version = 2, or it must be on Reader Version >= 3 and the feature columnMapping must exist in the protocol's readerFeatures.
• The table must be on Writer Version 7.
• The feature icebergCompatV3 must exist in the table protocol's writerFeatures.

This table feature is enabled when the table property delta.enableIcebergCompatV3 is set to true.

NOTE: Unlike IcebergCompatV1 and IcebergCompatV2, this feature does NOT forbid supporting and enabling Deletion Vectors on the table.

Writer Requirements for IcebergCompatV3

When this feature is supported and enabled, writers must:

• Require that Column Mapping be enabled and set to either name or id mode
• Require that Row Tracking to be enabled on the table.
  • Materialized Row ID column must use field ID 2147483540
  • Materialized Row Commit Version column must use field ID 2147483539
• Require that the nested element field of ArrayTypes and the nested key and value fields of MapTypes be assigned 32 bit integer identifiers. The requirement to ID allocation is the same as that in IcebergCompatV2.
• Require that IcebergCompatV1 and IcebergCompatV2 are not active on the table
• Require that partition column values be materialized when writing Parquet data files
• Require that all new AddFiles committed to the table have the numRecords statistic populated in their stats field
• Require writing timestamp columns as int64
• Block replacing partitioned tables with a differently-named partition spec
  • e.g. replacing a table partitioned by part_a INT with partition spec part_b INT must be blocked
  • e.g. replacing a table partitioned by part_a INT with partition spec part_a LONG is allowed