As data volumes grow exponentially, organizations need databases that can handle analytical queries across billions of rows in real time. ClickHouse is an open-source columnar database management system (DBMS) purpose-built for online analytical processing (OLAP). It is known for its exceptional query performance, making it one of the fastest analytical databases available.
Originally developed at Yandex to power its web analytics platform (Yandex.Metrica, the second-largest web analytics service in the world), ClickHouse was open-sourced in 2016 and has since grown into a widely adopted solution for real-time analytics across industries.
Key Features of ClickHouse
Columnar Storage: ClickHouse stores data by columns rather than rows, which enables highly efficient compression and allows analytical queries to read only the columns they need. This results in dramatically faster query execution for aggregations and scans.
Exceptional Query Performance: ClickHouse is designed to process analytical queries at speeds that often surpass other databases by orders of magnitude. It can scan billions of rows per second on a single server.
Real-Time Data Ingestion: ClickHouse supports high-throughput data ingestion, allowing you to insert millions of rows per second while simultaneously running analytical queries without performance degradation.
SQL Support: ClickHouse uses a SQL dialect that is familiar to most developers and analysts. It supports joins, subqueries, window functions, and a rich set of built-in functions for data analysis.
Scalability: ClickHouse scales both vertically and horizontally. It supports distributed query execution across clusters of servers, enabling linear scalability for both storage and compute.
Data Compression: Thanks to its columnar architecture and advanced compression algorithms, ClickHouse achieves compression ratios of 10x or more, significantly reducing storage costs.
Use Cases for ClickHouse
ClickHouse is widely adopted for demanding analytical workloads, including:
- Web and Product Analytics: Track user behavior, page views, and events at scale with sub-second query response times, powering dashboards and real-time reports.
- Log and Event Analytics: Analyze infrastructure logs, application events, and security data in real time, making ClickHouse a popular backend for observability platforms.
- Business Intelligence: Power BI dashboards and ad-hoc analytical queries across large datasets, enabling data-driven decision making.
- Time-Series Data: Store and analyze time-series data from IoT sensors, financial markets, or monitoring systems with high ingestion rates and fast aggregations.
- Ad Tech and Marketing Analytics: Process billions of ad impressions, clicks, and conversions to optimize campaigns and measure ROI in real time.
ClickHouse Cloud
ClickHouse Inc. offers ClickHouse Cloud, a fully managed service that eliminates the operational overhead of running ClickHouse clusters. It provides automatic scaling, built-in backups, and seamless upgrades, allowing teams to focus on analytics rather than infrastructure management. ClickHouse Cloud is available on AWS, Google Cloud, and Azure.