MORE secrets of ClickHouse Query Performance
ClickHouse is famously fast, but a small amount of extra work makes it much faster. Join us for the latest version of our popular talk on single-node ClickHouse performance. We start by examining the system log to see what ClickHouse…
ClickHouse Kafka Engine Tutorial
Our colleague Mikhail Filimonov just published an excellent ClickHouse Kafka Engine FAQ. It provides users with answers to common questions about using stable versions, configuration parameters, standard SQL definitions, and many other topics. Even experienced users are likely to learn…
Reducing Clickhouse Storage Cost with the LowCardinality Type – Lessons from an Instana Engineer
At Instana we are operating our Clickhouse clusters on m5.12xlarge AWS EC2 instances and similar sized custom build Google Cloud instances. The biggest cost driver however is not the size of the instance, but the EBS volumes / persistent SSDs…
ClickHouse Dictionaries, Reloaded!
ClickHouse external dictionaries are a “ClickHouse way” to handle multi-dimensional schema. ClickHouse Dictionaries Explained was the very first article in the Altinity blog three years ago. ClickHouse has improved significantly since then, and dictionaries have achieved a new level of…
SQL for ClickHouse DBA
My name is Meo and I’ve been a DataBase Administrator (DBA) for the last 35 years of my life. After getting a degree at the University in Turin (Italy) many years ago, I started working with relational databases, and I’m…
Monitoring ClickHouse on Kubernetes with Prometheus and Grafana
The ClickHouse Kubernetes operator is great at spinning up data warehouse clusters on Kubernetes. Once they are up, though, how can you see what they are actually doing? It’s time for monitoring!In this article we’ll explore how to configure two…
ClickHouse Kafka Engine FAQ
Kafka is a popular way to stream data into ClickHouse. ClickHouse has a built-in connector for this purpose — the Kafka engine. This article collects typical questions that we get in our support cases regarding the Kafka engine usage. We…