Manifest List
An Apache Iceberg metadata file representing one table snapshot. It lists the snapshot's manifest files with partition summaries, which enables time travel.
Manifest List is a metadata file in the Apache Iceberg format that represents a single snapshot of a table. It lists all the manifest files that make up that snapshot, providing a unified view of the table’s state.
How it Works
When a write transaction commits, Iceberg generates a new snapshot mapped to a manifest list.
- Snapshot Metadata: Contains the snapshot ID, parent snapshot ID, creation timestamp, and the summary of changes (e.g., records added).
- Manifest Tracking: Lists the file paths of all active manifest files associated with the snapshot.
- Partition Summary: Stores the range of partition values contained in each manifest file. Query engines scan these summaries to skip entire manifest files during query execution.
Lakehouse & Agentic Relevance
In a data lakehouse, manifest lists enable transaction isolation and time travel capabilities. Because each manifest list represents a complete snapshot, query engines can access previous table states. If an autonomous agent needs to query historical data or run transaction-consistent audits, it uses these snapshot states. Dremio queries the manifest list to identify the active files for any given snapshot, executing queries without locking the table.