Jaco van der Laan

Palantir’s Ontology, Kimball’s Star Schema, and Model-Driven Data Engineering: A Comparative View

23/09/2025  ·  Data Architecture

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How Palantir’s Ontology compares to Kimball’s dimensional modeling—and why a model-driven, historization-first architecture offers a more sustainable middle path.

Summary

Palantir’s Ontology is a highly normalized, business-oriented abstraction layer that aligns data around business objects and relationships. It contrasts with Kimball’s star schema, which organizes data into denormalized facts and dimensions optimized for reporting.

Our model-driven data engineering approach — grounded in historization, bi-temporal SCD2, and metadata-driven views — combines the best of both worlds: business semantics and history preservation (ontology) with pragmatic usability and performance (dimensional modeling).

What Palantir’s Ontology Is

Palantir describes its Ontology as the central semantic layer for its Foundry platform:

  • Data is modeled as business objects (Customer, Account, Contract, Product, Event).
  • Relationships between objects are first-class citizens.
  • Normalized, graph-like structure emphasizes consistency and semantics over query simplicity.
  • Built for lineage, governance, and composability — every data asset can be traced back to its source.

In essence, Ontology is an object-oriented view of enterprise data, aiming to bridge technical storage with business meaning.

Kimball’s Star Schema in Contrast

Kimball’s dimensional modeling, the foundation of most BI data warehouses, emphasizes:

  • Denormalization — facts (transactions, events) linked to dimensions (customer, product, time).
  • Simplicity and speed — easy for business users to query with tools like Tableau or Power BI.
  • Incremental delivery — each star schema can be built to deliver value quickly.

Strengths: pragmatic, user-friendly, performant for analytics.
Weaknesses: less semantic richness, poor at handling complex historization, and hard to evolve when business concepts change.

The Tension: Ontology vs. Star Schema

  • Ontology (Palantir): Strong semantics, normalized, but heavy upfront investment and more complex queries.
  • Star Schema (Kimball): Easy usability, but limited semantics and fragile with historical complexity.

This tension reflects a long-standing debate: do we optimize for business meaning or for business usability?

Where Model-Driven Data Engineering Fits

Our model-driven architecture offers a middle ground:

Historization as Foundation

Views as Abstractions

  • Like Palantir’s Ontology, we use metadata-driven exposure views (Designing Exposure Views) to present data in a business-oriented way.
  • But these are built on reproducible patterns, not proprietary tooling.

Separation of Concerns

  • Raw historized data is stored in staging / HSA / dual SCD2 layers.
  • Business-friendly, dimensional-style marts can be built as needed — without losing the underlying semantics.

Model-Driven Flexibility

  • Metadata and mappings drive the architecture (Metadata as Data).
  • This enables agility while preserving governance — something Palantir Ontology promises but locks into its platform.

Comparative Summary

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Why This Matters

Understanding the differences helps clarify your positioning:

  • Palantir Ontology shows the value of business semantics and relationships.
  • Kimball shows the value of usability and performance.
  • Our work brings the two together: a historization-first, metadata-driven approach where business semantics are preserved but exposed pragmatically.

In many ways, our dual SCD2 patterns, exposure views, and business-friendly mappings represent the “open-source ontology” that avoids Palantir’s lock-in while going beyond Kimball’s simplicity.

Conclusion

The debate between ontology vs. star schema is not new — it reflects two sides of the same coin: business semantics vs. business usability.

Our model-driven data engineering approach offers a third path:

  • Build on historization and bi-temporal SCD2 as the foundation.
  • Use metadata and mappings to define business meaning.
  • Expose data through views and marts that balance semantics and usability.

In short: ontology without the lock-in, star schema without the fragility.

📝 Summary

  • Palantir’s Ontology emphasizes business semantics and governance, while Kimball’s star schema emphasizes usability and speed.
  • A model-driven, historization-first architecture combines the best of both, preserving history and semantics while staying pragmatic and open.