whichdb
vs

Datahike vs XTDB

Datahike: Open-source, durable Datalog database for Clojure with Datomic-style immutable history. XTDB: Bitemporal SQL database on object storage that keeps every version of every row.

key differences

  • XTDB is built for larger datasets (≤ 10 TB) than Datahike (≤ 100 GB).
  • Horizontal scaling is none in Datahike and manual in XTDB.
  • Only Datahike has secondary indexes, in-memory.
  • Only XTDB has json, columnar storage, compression.
  • Datahike can run embedded in your application process.

choose datahike for

  • +Clojure apps wanting Datalog and history without Datomic
  • +Knowledge graphs and research data with provenance
  • +Embedded databases in ClojureScript apps

best at · OLTP, Knowledge graph, Embedded

choose xtdb for

  • +Financial and insurance systems needing as-of reporting
  • +Audit trails with retroactive corrections
  • +Event-sourced systems wanting SQL over history

best at · OLTP, Event sourcing, Ledger

DatahikeOpen-source, durable Datalog database for Clojure with Datomic-style immutable history.
XTDBBitemporal SQL database on object storage that keeps every version of every row.
overview
Primary model
Relational
Relational
Also supports
Graph
Document, Columnar / OLAP
Type
Database engine
Database engine
Status
Active
Active
Developer
replikativ (Christian Weilbach and contributors)
JUXT Ltd
First release
2018
2019
Latest version
0.8.1913 (Oct 26, 2026)
2.2.0 (Oct 21, 2026)
License
Open source (copyleft)Eclipse Public License 1.0
Open source (copyleft)Mozilla Public License 2.0
Free tier
✓
✓
popularity
WhichDB Score
5.8
8.3
Rank
#374
#328
GitHub stars
1.9K
3.1K
Stack Overflow questions
–
7
scale & guarantees
Comfortable data size
Small (≤ 100 GB)
Medium (≤ 10 TB)
Horizontal scaling
None
Manual
Multi-region
None
None
ACID
Full
Full
Consistency
Strong
Strong
Schema
Flexible
Flexible
Architecture
Embedded, Client server
Distributed, Shared storage
deployment
Self-hosted
✓
✓
Vendor-managed cloud
—
—
Serverless
—
—
Embedded
✓
—
Edge
—
—
Clouds
–
–
capabilities
Transactions
✓
✓
Joins
✓
✓
Secondary indexes
✓
—
Full-text search
—
—
Vector search
—
—
Geospatial
—
—
JSON
—
✓
Change data capture
—
—
Triggers
—
—
Stored procedures
—
—
Materialized views
—
—
TTL / expiry
—
—
Pub/Sub
—
—
Columnar storage
—
✓
In-memory
✓
—
Durable persistence
✓
✓
Compression
—
✓
Encryption at rest
—
—
Role-based access
—
—
Time travel
✓
✓
Branching
—
—
Online schema changes
—
—
Streaming ingest
—
—
Offline sync
—
—
Runs in WebAssembly
—
—
interfaces
Query languages
Datalog, Pull API
SQL, XTQL
Client languages
Clojure, ClojureScript, Java
Java, Kotlin, Clojure, Python, JavaScript, Go
Best for
OLTP, Knowledge graph, Embedded
OLTP, Event sourcing, Ledger, HTAP
Add more to this comparisonNot sure either fits? Try smart match

Datahike vs XTDB: FAQ

What is the difference between Datahike and XTDB?

Datahike: Open-source, durable Datalog database for Clojure with Datomic-style immutable history. XTDB: Bitemporal SQL database on object storage that keeps every version of every row. XTDB is built for larger datasets (≤ 10 TB) than Datahike (≤ 100 GB). Horizontal scaling is none in Datahike and manual in XTDB. Only Datahike has secondary indexes, in-memory.

When should I choose Datahike over XTDB?

Choose Datahike for clojure apps wanting Datalog and history without Datomic; knowledge graphs and research data with provenance; and embedded databases in ClojureScript apps. Choose XTDB for financial and insurance systems needing as-of reporting; audit trails with retroactive corrections; and event-sourced systems wanting SQL over history.

Is Datahike or XTDB more popular?

XTDB ranks #328 on the WhichDB Score (8.3/100) and Datahike ranks #374 (5.8/100). Popularity is not fit: check the requirements that matter for your project.

Are Datahike and XTDB open source?

Yes. Datahike is open source. License: Eclipse Public License 1.0. Yes. XTDB is open source. License: Mozilla Public License 2.0.