KsqlDB
ksqlDB is a tool that allows you to analyse and process live data streams using simple, database-like commands.
Platform availability
Available on 0 of 6 install platforms
- Unraid (not listed)
- TrueNAS (not listed)
- Umbrel (not listed)
- ZimaOS (not listed)
- Proxmox (not listed)
- Helm (not listed)
Health score?A 0-100 score computed nightly from four factors: maintained (40%: recent commits and steady activity), popular (25%: GitHub stars, log scale), easy to install (20%: platforms, install notes, setup guides, Docker image) and light to run (15%: minimum RAM, ARM support). When the source code has been checked, a fifth factor, security check (20%: automated scan for committed secrets, unsafe desktop-app settings, known-vulnerable dependencies and project hygiene; any serious finding caps it at 20), is added. Factors without data are left out and the rest are rescaled.
59/100 Fair
- Maintained
- 100last commit 12 days ago
- Popular
- 50315 GitHub stars
- Easy to install
- 250 install platforms, install notes, Docker image
- Light to run
- 108 GB minimum RAM
- GitHub stars
- 315
- Open issues
- 1331
- Last commit
- 2026-09-28
- Latest release
- v0.6.0-docs
- Activity
- steady
Checked 12 days ago - source: GitHub (confluentinc/ksql)
Resources & Compatibility
Minimum requirements: 8 GB RAM.
Checked 12 days ago - source: Docker Hub image tags and published docs
First-install notes
- Set the two key connection settings In your ksql-server.properties file, set bootstrap.servers to your Kafka broker address (the message broker ksqlDB connects to), such as localhost:9092, and listeners to the address and port ksqlDB should answer on, such as http://localhost:8088. If these are wrong, ksqlDB can’t talk to Kafka and clients can’t reach it. source
- Start the server with that file Run <path-to-confluent>/bin/ksql-server-start <path-to-confluent>/etc/ksqldb/ksql-server.properties, replacing the placeholder with the folder where Confluent is installed. This makes the server use the settings you just edited instead of default guesses that may not match your Kafka broker. source
- Check logs if using Docker If you installed ksqlDB with Docker, view the container logs after starting it to see whether the server begins. If it fails, the logs usually show what went wrong before you try connecting. source
- Prerequisite Connect ksqlDB to an Apache Kafka instance, as it processes data from Kafka topics. source
Fetched today - each note links to its source
Variants
Alternatives
No alternatives collected yet.
Common questions
Which settings control ksqlDB's connection to Kafka and how do I start it with them?
In ksql-server.properties, set bootstrap.servers to the Kafka broker address and listeners to the address and port ksqlDB should answer on. Then run ksql-server-start with the path to that properties file.
What should I check if a Dockerized ksqlDB instance does not start?
View the container logs after starting the container. The logs usually show what went wrong before you try connecting.
How are ksqlDB materialized views updated and queried?
Materialized views are created by persistent queries that maintain incrementally updated results in a table. The results can be pulled with SELECT queries or pushed continuously with streaming SELECT queries.
Can ksqlDB use Kafka Connect sources and sinks?
Yes, ksqlDB includes Connect and can integrate with any Kafka Connect data source or sink from within ksqlDB.
How does ksqlDB handle query state according to community experience?
A community discussion says KSQL/Kafka Streams does not have the entire state saved out and must read every message in the topic, partitioned and distributed, to the last commit.
Answers sourced from github.com, github.com, github.com, www.reddit.com
Community
- Why I Recommend My Clients NOT Use KSQL and Kafka Streams - Reddit (reddit)
- Can Flink succeed where ksqlDB failed? An open discussion ... - Reddit (reddit)
Collected 6 days ago - public community threads