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Lakehouse tables

Open lakehouse table formats are first-class citizens, not a secondary export path. Delta and Iceberg ship together, co-equal, and the table format is a deployment policy a cell chooses from configuration, not a rewrite and not a house format a customer is locked into.

In one paragraph​

We publish and share in open formats, bring your own engine. Delta and Iceberg are co-equal and the table format is a deployment policy; both read zero-copy over object storage; and external sharing runs over both the Delta Sharing protocol and the Iceberg REST catalog, under one governance model.

Format neutrality​

Format neutrality is the differentiator here, and it is concrete:

  • Both formats ship as core dependencies. The boot path prefers neither.
  • A single policy setting chooses the default, and a per-table choice overrides it. An Iceberg-primary sovereign cell boots from configuration alone, no code change.
  • Both read zero-copy over object storage: the cell's own object store, or external S3, GCS, or Azure, so a reader is not paying a copy to consume a table.

A cell writes and merges tables in both formats, with a format-agnostic core underneath (commits, deletion vectors, predicates, table clone) carrying the format-specific layers above it.

*Figure C6: one lakehouse core, two co-equal formats. A single deployment policy setting chooses the default format (a per-table choice still overrides it); Apache Iceberg and Delta Lake sit co-equal on one format-agnostic core, joined by a bidirectional metadata bridge so either is queryable through the other; and both read zero-copy over object storage, the data stays where it lives.

Table equivalent

ElementRoleNotes
Deployment policy settingChooses the default table formatPer-table override allowed; boots from configuration alone (no code change)
Format-agnostic coreCarries commits, deletion vectors, predicates, table cloneThe neutral layer beneath both formats
Apache IcebergCo-equal open formatRead and write
Delta LakeCo-equal open formatRead and write
Bidirectional metadata bridgeDelta ↔ Iceberg metadata conversionEither format queryable through the analytical path
Object storageWhere the bytes liveZero-copy read: cell store, S3, GCS, or Azure

What each format brings​

FormatNotable surface
Apache IcebergSchema fields and partition transforms, sort orders, snapshot management (create, expire, rollback), schema and partition evolution, manifest and data-file management across Parquet/ORC/Avro, table maintenance, and a REST metadata catalog.
Delta LakeA JSON transaction log and version management, branch management for concurrent workflows, checkpoints, row lineage, variant type for semi-structured data, native geospatial types, and the Delta Sharing protocol.
InteroperabilityBidirectional Delta ↔ Iceberg metadata conversion and analytical-engine bridges, so either format is queryable through the analytical path.

Honesty about scope​

The claim to make here is format neutrality and zero-copy read parity between the two open formats, plus open sharing. Two claims sit deliberately outside that ceiling:

What not to read into this
  • Format neutrality, precisely. The claim is neutrality between the two open formats, Iceberg and Delta at parity, which is a different and more useful property than matching any single vendor platform feature for feature.
  • Not a performance claim. The acceleration layer that makes a lakehouse fast, file pruning, row-group statistics, Bloom filters, Z-ordering, projection indexes, and related data-skipping, is built but is not in the production read path, so no performance or benchmark claim attaches to the open formats.

Nothing in the platform is graded, certified, or deployed against a reference customer; these pages describe mechanisms, not proven results.

Across the deployment matrix​

  • Single-cell and multi-cell, tables live in the cell's stores and read zero-copy locally or across cells.
  • Sovereign / air-gapped, an Iceberg- or Delta-primary sovereign cell is a configuration choice; no external service is required to read a table.
  • Cloud-enabled: external object stores are available as an option.