whichdb
vs

chDB vs DuckDB

chDB: Embedded, in-process OLAP engine powered by ClickHouse, used mainly from Python. DuckDB: In-process columnar SQL database: the SQLite of analytics, running inside your app or notebook.

key differences

  • Transactions: chDB offers none ACID; DuckDB offers full.
  • Only DuckDB has transactions, secondary indexes, full-text search, vector search, encryption at rest.

choose chdb for

  • +Notebook analytics with ClickHouse SQL
  • +Local ETL on Parquet and CSV
  • +Testing ClickHouse queries without a server
  • +Embedding analytics in Python services

best at · OLAP, Embedded

choose duckdb for

  • +Local data analysis in notebooks
  • +ETL and data-engineering pipelines on files
  • +Embedded analytics inside applications
  • +Querying data lakes on S3 without a cluster

best at · OLAP, Embedded, Lakehouse

chDBEmbedded, in-process OLAP engine powered by ClickHouse, used mainly from Python.
DuckDBIn-process columnar SQL database: the SQLite of analytics, running inside your app or notebook.
overview
Primary model
Columnar / OLAP
Columnar / OLAP
Also supports
Relational, Document
Relational, Document, Spatial, Vector
Type
Database engine
Database engine
Status
Active
Active
Developer
ClickHouse, Inc.
DuckDB Foundation / DuckDB Labs
First release
2023
2019
Latest version
4.4.0 (Sep 11, 2026)
2.0.0 (Oct 21, 2026)
License
Open source (permissive)Apache License 2.0
Open source (permissive)MIT License
Free tier
✓
✓
popularity
WhichDB Score
21.1
63.7
Rank
#143
#13
GitHub stars
2.9K
42.6K
Stack Overflow questions
–
501
scale & guarantees
Comfortable data size
Medium (≤ 10 TB)
Medium (≤ 10 TB)
Horizontal scaling
None
None
Multi-region
None
None
ACID
None
Full
Consistency
Strong
Strong
Schema
Strict
Strict
Architecture
Embedded, In memory, Single node
Embedded, Single node, In memory
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
SQL (ClickHouse dialect), Python DataFrame API
SQL (PostgreSQL-like dialect)
Client languages
Python, Go, Rust, JavaScript, C, Bun
Python, R, Java, JavaScript, Go, Rust, C, Swift
Best for
OLAP, Embedded
OLAP, Embedded, Lakehouse, Warehouse
Add more to this comparisonNot sure either fits? Try smart match

chDB vs DuckDB: FAQ

What is the difference between chDB and DuckDB?

chDB: Embedded, in-process OLAP engine powered by ClickHouse, used mainly from Python. DuckDB: In-process columnar SQL database: the SQLite of analytics, running inside your app or notebook. Transactions: chDB offers none ACID; DuckDB offers full. Only DuckDB has transactions, secondary indexes, full-text search, vector search, encryption at rest.

When should I choose chDB over DuckDB?

Choose chDB for notebook analytics with ClickHouse SQL; local ETL on Parquet and CSV; and testing ClickHouse queries without a server. Choose DuckDB for local data analysis in notebooks; ETL and data-engineering pipelines on files; and embedded analytics inside applications.

Is chDB or DuckDB more popular?

DuckDB ranks #13 on the WhichDB Score (63.7/100) and chDB ranks #143 (21.1/100). Popularity is not fit: check the requirements that matter for your project.

Are chDB and DuckDB open source?

Yes. chDB is open source. License: Apache License 2.0. Yes. DuckDB is open source. License: MIT License.