Database & Data Management · head to head
Cassandra vs ClickHouse
Cassandra
Database & Data Management
Manage massive amounts of data with linear scalability
- From
- Free
- Rated
- -
ClickHouse
Database & Data Management
Fast open-source column-oriented database for real-time analytics
- From
- Free
- Rated
- -
The short version
- Each has a real cost: Cassandra no support for joins across tables; ClickHouse limited multi-row atomic transactions and expensive UPDATE/DELETE operations unsuitable for transactional systems
- They diverge on capability: Cassandra covers Fault Tolerance, ClickHouse covers Column-oriented Storage.
Where they differ
Only the attributes on which Cassandra and ClickHouse actually diverge.
| Attribute | Cassandra | ClickHouse |
|---|---|---|
| Platforms | Linux, macOS, Windows, Docker, Kubernetes | Linux, macOS, Windows (via Docker) |
| Founded | 2008 | 2021 |
Identical on both: starting price (Free), pricing model (Unknown), free tier (Yes), user rating (Not yet rated), category (Database & Data Management).
What each one covers
Drawn from each product's published feature list. An absence here means we hold no record of it - not that the product lacks it.
Only in Cassandra
- Fault Tolerance
- Multi-datacenter Replication
- Tunable Consistency
- CQL Query Language
- Distributed Architecture
- No Single Point of Failure
- DataStax
- Apache Spark
Only in ClickHouse
- Column-oriented Storage
- Real-time Analytics
- SQL Support
- Data Compression
- Vectorized Query Execution
- Approximate Calculations
- Kafka
- S3
Both cover
- Linear Scalability
- Linux support
- Mac support
- Docker support
What people use each for
The jobs each tool is most often brought in to do.
Cassandra
- Real-time applicationsnot ClickHouse
- Content managementnot ClickHouse
- User profilesnot ClickHouse
- Mobile backendsnot ClickHouse
- Cachingnot ClickHouse
ClickHouse
- Business intelligencenot Cassandra
- Data warehousingnot Cassandra
- Real-time analyticsnot Cassandra
- Reportingnot Cassandra
- Machine learningnot Cassandra
Where each one falls short
Documented limitations, not opinions. Every one is a constraint you would hit in normal use.
Cassandra
- No support for joins across tables
- No ACID transactions across multiple rows
- Data model must be designed around query patterns upfront, making schema evolution difficult
- Partition key misconfigurations can cause uneven data distribution and hotspots that degrade performance
ClickHouse
- Limited multi-row atomic transactions and expensive UPDATE/DELETE operations unsuitable for transactional systems
- Requires upfront schema design discipline with MergeTree engine choices and sort/partition keys
- Experimental vector search support, not production-ready for vector operations
- Different query syntax from standard SQL requiring migration planning
- Limited JOIN capabilities compared to traditional relational databases
- Migration complexity with 2-4 weeks estimated for data type mapping and query translation
Pricing, plan by plan
Cassandra
FreeNo published plan breakdown. See the Cassandra review.
ClickHouse
FreeNo published plan breakdown. See the ClickHouse review.
Which should you pick?
Choose Cassandra if
- You need fault tolerance.
- You want to start without paying.
- You work on Linux, macOS, Windows, Docker, Kubernetes.
- You also want multi-datacenter replication.
Choose ClickHouse if
- You need column-oriented storage.
- You want to start without paying.
- You work on Linux, macOS, Windows (via Docker).
- You also want real-time analytics.
Questions people ask
- Is Cassandra or ClickHouse better?
- Neither clearly leads. Cassandra starts at Free and ClickHouse at Free, and user ratings are close enough to be indistinguishable. Choose on capability and platform support.
- Which is cheaper, Cassandra or ClickHouse?
- Cassandra starts at Free and ClickHouse at Free.
- Does Cassandra or ClickHouse run on more platforms?
- Cassandra runs on Linux, macOS, Windows, Docker, Kubernetes. ClickHouse runs on Linux, macOS, Windows (via Docker).
- Can I use Cassandra for free?
- Both have a free tier, so you can try either at no cost before committing.
- What is Cassandra best used for?
- Cassandra is most often used for real-time applications, content management, user profiles, mobile backends. Of those, real-time applications and content management are not what ClickHouse is typically brought in for.
- What can Cassandra do that ClickHouse cannot?
- Cassandra covers Fault Tolerance, Multi-datacenter Replication, Tunable Consistency, CQL Query Language. ClickHouse covers Column-oriented Storage, Real-time Analytics, SQL Support, Data Compression. Both handle Linear Scalability, Linux support, Mac support, Docker support.
Answered from the vendors’ own pages
Cassandra: Does Cassandra support joins between tables?
No. Cassandra does not support joins or foreign keys. The data model requires denormalization, meaning data must be duplicated across tables to support different query patterns.
SourceClickHouse: What is ClickHouse best used for?
ClickHouse is optimized for analytical workloads on large datasets. It excels at fast aggregations and queries, being 10-100x faster than PostgreSQL on large aggregations.
SourceCassandra: Does Cassandra offer ACID transactions?
No. Cassandra provides only row-level atomicity and isolation, not full ACID transactions across multiple rows or tables. It uses lightweight transactions via Paxos for per-row compare-and-set operations.
SourceClickHouse: Does ClickHouse support transactions?
ClickHouse has limited transaction support and expensive UPDATE/DELETE operations. It is not suitable for transactional workloads requiring strict ACID guarantees.
SourceCassandra: What programming languages can connect to Cassandra?
Cassandra supports official drivers for multiple languages including Python, Java, Node.js, and Go, allowing applications to communicate via the native Cassandra protocol.
SourceClickHouse: How does ClickHouse compare to PostgreSQL?
ClickHouse is 10-100x faster for analytics but PostgreSQL is better for transactional workloads. Many teams use both: PostgreSQL for writes via MaterializedPostgreSQL replication to ClickHouse for analytics.
SourceCassandra: Can I deploy Cassandra in the cloud?
Yes. Cassandra can run on any cloud platform (AWS, Google Cloud, Azure) via Docker, virtual machines, or managed services like DataStax Astra DB, which provides a fully managed DBaaS option.
SourceCassandra: Does Cassandra have a free option?
The open source Apache Cassandra is free. DataStax also offers Astra DB with a free tier providing up to 25GB storage and 25 million read/write operations per month.
Source