ClickHouse Newsletter

A new database research lab, an interactive playground for over 100 databases, and our biggest release post ever - it’s just your average month in the world of ClickHouse!

In this issue, meet Andy Pavlo, the newest member of the ClickHouse team, learn about what’s new in 26.7, and catch up on the latest in ClickHouse Managed Postgres, observability, vector search, and more.

And don’t forget to register for the Open House Roadshow, which is visiting six cities over the next six weeks.

Inside this issue

• Featured community member: Manuel Raimann
• Open House Roadshow
• 26.7 release
• Andy Pavlo joins ClickHouse to establish ClickHouse Labs
• Your TTL is working. That might be the problem.
• Alexey created a playground for 110 database systems
• Postgres vs ClickHouse is the wrong question. I use both.
• What's new in ClickHouse Managed Postgres: Customer notifications, better observability, faster backups, extensions, and more
• How we build and evaluate our MCP server for SRE agents
• Quick reads
• Upcoming events

Featured community member

This month's featured community member is Manuel Raimann, Head of Engineering at Redact.dev.

Manuel contributed a series of performance improvements in the recent ClickHouse 26.7 release. His work sped up wide-integer comparisons by up to 7×, Delta decompression by up to 5×, and statistical and bitwise aggregates by up to 4×. He also made numeric array operations and primary-key index filtering faster.

Apart from contributing to ClickHouse, he also contributes to the open-source Deadlock API, which provides game data and analytics for Deadlock, Valve’s upcoming game combining third-person shooting with MOBA-style gameplay.

➡️ Connect with Manuel on LinkedIn

Open House Roadshow

The Open House Roadshow continues, with visits to Amsterdam (Sep 1), Singapore (Sep 24), and London (Sep 30).

Each stop will feature talks from both ClickHouse employees and customers, as well as optional training workshops.

We’ll also be visiting New York City, Bangalore, and Munich.

➡️ See all Open House locations

26.7 release

The 26.7 release blog post is our longest one yet. While there is certainly value in brevity, we’re going to let ourselves off this time because there were so many features that we needed to tell you about!

As always, we have join optimizations. The hash join algorithm has been made more efficient by reducing the probe-side input and shrinking build-side hash tables. ClickHouse will now also automatically choose how to arrange joins in a multi-table query.

Text indexes now store token positions, a feature that’s needed for efficient phrase search. We tested it on a Hacker News dataset, and a query for the phrase "Google web search" was 40 times faster.

The EXPLAIN clause has a new member: EXPLAIN ANALYZE, which runs every query-processing phase before discarding the result rows and annotating the logical execution-plan tree with measurements collected during actual execution.

That’s just a brief taster - we’ll let you read the blog post to find out the rest!

➡️ Read the release post

Andy Pavlo joins ClickHouse to establish ClickHouse Labs

The news of the month (and maybe the year?!) is that Andy Pavlo is joining ClickHouse to establish ClickHouse Labs. Andy was previously a professor in the Computer Science Department at Carnegie Mellon University since 2013.

ClickHouse Labs is an applied research lab that will conduct scientifically valuable research and then help transform the best ideas into technology that matters to users.

In addition to developing ideas to improve ClickHouse, the lab will work with the ClickHouse PostgreSQL team to help establish its managed service as a market leader in performance and reliability.

➡️ Read the blog post

Your TTL is working. That might be the problem.

Amrelboridy’s disk kept filling up, but there wasn’t any indication why. There weren’t any orphaned or detached parts, and data retention was healthy.

In this blog post, Amrelboridy explains what happens in ClickHouse when a row’s Time To Live (TTL) expires and how configuring the partition key can save you a lot of headaches.

➡️ Read the blog post

Alexey created a playground for 110 database systems

Alexey has extended ClickBench, a benchmark for analytical databases, to include an interactive playground where you can run ad hoc queries on the 100m-record ClickBench dataset against over 100 database systems.

The playground runs on Firecracker microVMs on an AWS EC2 instance, and in the blog post, Alexey explains why this was the only approach that provided strong isolation, reasonable cost, and fast startup.

➡️ Read the blog post

Postgres vs ClickHouse is the wrong question. I use both.

Artem Senenko explains that “Postgres vs ClickHouse” is the wrong question because the databases solve different problems.

He uses Postgres for mutable data, such as monitors, incidents, teams, and configuration. But the continuously growing stream of immutable check results goes into ClickHouse for efficient storage and fast analytical queries.

The majority of the blog post focuses on ways to optimize ClickHouse, including compression codecs, tenant-aware sort keys, per-row retention periods, and materialized views that pre-aggregate data for dashboards.

➡️ Read the blog post

What's new in ClickHouse Managed Postgres: Customer notifications, better observability, faster backups, extensions, and more

In the latest issue of What’s New in ClickHouse Managed Postgres, we introduce a smoother onboarding experience, proactive storage notifications, richer observability, and faster, more predictable backups for databases larger than 10 TB.

We’ve also expanded the extension ecosystem: pg_re2 makes regular-expression queries up to 9× faster, while improvements to pg_clickhouse and pg_stat_ch enable more efficient analytics and query monitoring across Postgres and ClickHouse.

➡️ Read the blog post