Concepts
DataChain is built around a small number of ideas. Understanding them makes the entire API predictable. Start with Data Memory and Datasets, then explore deeper topics as needed.
- Data Memory: the accumulated record of everything the team has done with its data, composed of versioned, typed datasets, queryable at warehouse speed; operational, not declarative
- Datasets: the atom of memory: named, versioned, typed, immutable; the unit of persistence, sharing, compounding, and reasoning
- Chain: query combining Python and SQL execution in one composable chain; lazy, optimized, atomic
- Files and Types: the File abstraction, modality types, annotation types, and the type system
- Compute Engine: heavy Python work over files in object storage; parallel, async, distributed, checkpoint-recoverable; the only layer that produces what does not yet exist
- Knowledge Base: the compilation layer that turns persistent datasets into agent-readable knowledge; derived from Data Memory via LLM enrichments
- Skill and MCP: the delivery surface that reaches Claude Code, Cursor, and Codex; agents read context here while pipelines write through the Python library