System Column Registry

Metaxy reserves a small set of system-managed columns that it attaches to feature metadata tables. These columns are part of the platform contract and are used by the metadata store, versioning engine, and migration tooling to keep track of feature lineage.

All system column names start with the metaxy_ prefix to avoid collisions with user-defined feature fields. Only the prefixed forms are supported.

Canonical column names

Canonical name	Description
metaxy_provenance_by_field	Struct capturing per-field provenance hashes. Sample level.
metaxy_feature_version	Version of the versioned graph upstream to the feature.
metaxy_snapshot_version	Version of the entire feature graph for the Metaxy project.
metaxy_feature_spec_version	Version of the feature spec part responsible for graph topology.
metaxy_feature_tracking_version	Hash that combines spec version and project for multi-project tracking.