Hello, and welcome to the January 2026 ClickHouse newsletter!

This month, we learn how chDB achieved true zero-copy integration with Pandas DataFrames, how WKRP migrated their RuneScape tracking plugin from TimescaleDB to ClickHouse, replacing Apache Flink with ClickHouse's Kafka engine, and more!

## Featured community member: lgbo {#featured-community-member}

This month's featured community member is lgbo.

![jan20026_image5.png](/uploads/jan20026_image5_7e4ba288f9.png)

lgbo works at BIGO, where they use ClickHouse in their real-time data pipeline that processes tens of billions of messages daily.

lgbo has submitted several pull requests to address performance issues, including reducing memory usage for window functions, reducing cache misses during hash table iteration, and optimizing CROSS JOINs.

lgbo also improved short-circuit execution performance by avoiding unnecessary operations on non-function columns, added a new stringCompare function for lexicographic comparison of substring portions, and fixed a bug where named tuple element names weren't preserved correctly during type derivation.

➡️ <a href="https://github.com/lgbo-ustc" target="_blank">Follow lgbo on GitHub</a>

## 25.12 release {#release}

![jan20026_image6.png](/uploads/jan20026_image6_a0edc2e602.png)

ClickHouse 25.12 delivers significant improvements in query performance across the board. We have faster top-N queries through data skipping indexes, a reimagined lazy reading execution model that's 75 times faster, and a more powerful DPsize join reordering algorithm.

➡️ <a href="https://clickhouse.com/blog/clickhouse-release-25-12" target="_blank">Read the release post</a>

## The Journey to Zero-Copy: How chDB Became the Fastest SQL Engine on Pandas DataFrame {#chdb}

![jan20026_image7.png](/uploads/jan20026_image7_1d3f81a67a.png)

chDB v4.0 achieves true zero-copy integration with Pandas DataFrames. By eliminating serialization steps and implementing direct memory sharing between ClickHouse and NumPy, queries that previously took 30 seconds now complete in under a second.

➡️ <a href="https://clickhouse.com/blog/chdb-journey-to-zero-copy" target="_blank">Read the blog post</a>

## A small-time review of ClickHouse {#clickhouse_review}

WKRP migrated their RuneScape tracking plugin from TimescaleDB to ClickHouse with impressive results. Storage usage improved dramatically: location data compressed from 4.28 GiB to 592 MiB (87% reduction), while XP tracking data went from 872 MiB to 168 MiB (81% reduction). Beyond storage, the migration simplified operations - upgrades now happen through the package manager without coordinated downtime.

The verdict: "Timescale worked well, but ClickHouse has provided better performance and made running the service easier."

➡️ <a href="https://www.wkrp.xyz/a-small-time-review-of-clickhouse/" target="_blank">Read the blog post</a>

## Solving the "Impossible" in ClickHouse: Advent of Code 2025 {#advent_of_code}

![jan20026_image1.png](/uploads/jan20026_image1_245b4653d7.png)

Yes, we're still talking about Christmas in mid-January, but Zach Naimon's deep dive into solving Advent of Code 2025 entirely in ClickHouse SQL is worth the delayed celebration.

Following strict rules (pure SQL only, raw inputs, single queries), Zach tackled all 12 algorithmic puzzles that typically require Python, Rust, or C++. The solutions showcase ClickHouse's versatility through recursive CTEs for pathfinding, arrayFold for state machines, and specialized functions like intervalLengthSum for geometric problems.

Proof that with the right tools, "impossible" problems become just another data challenge.

➡️ <a href="https://clickhouse.com/blog/clickhouse-advent-of-code-2025" target="_blank">Read the blog post</a>

## Seven Companies, One Pattern: Why Every Scaled ClickHouse Deployment Looks the Same {#seven_companies}

Luke Reilly explains why Uber, Cloudflare, Instacart, GitLab, Lyft, Microsoft, and Contentsquare all build the same four-layer abstraction stack over ClickHouse: it changes cost curves.

Platform teams absorb schema optimization knowledge once through semantic layers and query translation engines, enabling sublinear scaling - headcount grows with data volume instead of user count.

Now AI is becoming the fifth layer, with tools like ClickHouse.ai and MCP servers adding natural language interfaces on top of these semantic definitions.

➡️ <a href="https://medium.com/@lureilly1/seven-companies-one-pattern-why-every-scaled-clickhouse-deployment-looks-the-same-d2ba68606ad6" target="_blank">Read the blog post</a>

## Your AI SRE needs better observability, not bigger models {#ai_sre}

![jan20026_image2.png](/uploads/jan20026_image2_f3bbf2f869.png)

Drawing on his experience increasing Confluent's availability from 99.9% to 99.95%, Manveer Chawla explains why AI SRE copilots should prioritize investigation over auto-remediation. Most AI SRE tools fail because they're built on observability platforms with short retention, dropped high-cardinality dimensions, and slow queries.

The solution? Rethink the observability architecture. Manveer details a reference architecture using ClickHouse that demonstrates the effectiveness of AI copilots, which require better data foundations, rather than larger models.

➡️ <a href="https://clickhouse.com/blog/ai-sre-observability-architecture" target="_blank">Read the blog post</a>

## Simplifying real-time data pipelines: How ClickHouse replaced Flink for our Kafka Streams {#kafka_streams}

![jan20026_image4.png](/uploads/jan20026_image4_df92d08407.png)

Ashkan Goleh Pour provides a detailed walkthrough of replacing Apache Flink with ClickHouse's native Kafka integration for real-time streaming.

The architecture uses ClickHouse's Kafka table engine to consume events directly, Materialized Views for continuous SQL transformations, and MergeTree tables for persistent state, thereby eliminating the need for external stream processors.

➡️ <a href="https://medium.com/towards-data-engineering/simplifying-real-time-data-pipelines-how-clickhouse-replaced-flink-for-our-kafka-streams-13f6f4e1e097" target="_blank">Read the blog post</a>

## Quick reads {#quick-reads}

* Georgii Baturin has written a multi-part series of posts showing <a href="https://medium.com/hands-on-dbt-with-clickhouse/hands-on-dbt-with-clickhouse-7-why-tests-matter-and-why-a-green-build-does-not-prove-anything-by-c15f1cb1264d" target="_blank">how to use dbt with ClickHouse</a>.
* Shuva Jyoti Kar demonstrates <a href="https://medium.com/@shuva.jyoti.kar.87/the-speed-of-thought-real-time-analytics-meets-agentic-ai-1864e1ed6165" target="_blank">how to build an autonomous AI agent system</a> by connecting ClickHouse with Google's Gemini CLI using the Model Context Protocol (MCP).
* Gulled Hayder shows <a href="https://medium.com/@aagulled/getting-clickhouse-ready-for-web-traffic-analysis-6bec9867e1ee" target="_blank">how to set up ClickHouse on a Linux system</a> with Python, install and configure the database with proper authentication, generate 1 million rows of synthetic web traffic data, and load it into a MergeTree table for analytics.
* ByteBoss [builds a real-time cryptocurrency market data pipeline](https://medium.com/@ByteBosss/building-a-real-time-cryptocurrency-market-data-pipeline-from-scratch-9c81acf3f75b) that connects to exchange WebSockets (Binance/Coinbase), normalizes their different data formats, streams through Kafka/Redpanda, automatically processes with ClickHouse materialized views, and visualizes live trading data in Grafana dashboards.

## Interesting projects {#interesting-projects}

* <a href="https://github.com/arniwesth/DoomHouse" target="_blank">DoomHouse</a> - An experimental "Doom-like" game engine that renders the 3D graphics entirely in ClickHouse SQL.
* <a href="https://hub.docker.com/r/genezhang/clickgraph" target="_blank">genezhang/clickgraph</a> - Stateless, read-only graph query engine for ClickHouse using Cypher.
* <a href="https://github.com/ppiankov/clickspectre" target="_blank">clickspectre</a> - A spectral ClickHouse analyzer that tracks which tables are actually used and by whom.

## Upcoming events {#upcoming-events}

### Virtual training

* <a href="https://clickhouse.com/company/events/202602-amer-clickhouse-admin-workshop" target="_blank">ClickHouse Admin Workshop</a> - 12th February
* <a href="https://clickhouse.com/company/events/202602-amer-emea-query-optimization" target="_blank">ClickHouse Query Optimization Workshop</a> - 19th February

**Real-time Analytics**

* <a href="https://clickhouse.com/company/events/202601-EMEA-Real-time-Analytics-with-ClickHouse-Level2" target="_blank">Real-time Analytics with ClickHouse: Level 2</a> - 21st January
* <a href="https://clickhouse.com/company/events/202601-EMEA-Real-time-Analytics-with-ClickHouse-Level3" target="_blank">Real-time Analytics with ClickHouse: Level 3</a> - 28th January

**Observability**

* <a href="https://clickhouse.com/company/events/202601-APJ-Observability-with-ClickStack-Level1" target="_blank">Observability with ClickStack: Level 1</a> (APJ time) - 27th January
* <a href="https://clickhouse.com/company/events/202601-APJ-Observability-with-ClickStack-Level2" target="_blank">Observability with ClickStack: Level 2</a> (APJ time) - 29th January
* <a href="https://clickhouse.com/company/events/202602-AMER-Observability-with-ClickStack-Level1" target="_blank">Observability with ClickStack: Level 1</a> - 4th February
* <a href="https://clickhouse.com/company/events/202602-AMER-Observabiity-with-ClickStackLevel2" target="_blank">Observability with ClickStack: Level 2</a> - 5th February

### Events in AMER

* <a href="https://luma.com/abggijbh" target="_blank">Iceberg Meetup in Menlo Park</a> - 21st January
* <a href="https://luma.com/ifxnj82q" target="_blank">Iceberg Meetup in NYC</a> - 23rd January
* <a href="https://luma.com/iicnlq41" target="_blank">New York Meetup</a> - 26th January
* <a href="https://clickhouse.com/company/events/webinar-true-cost-of-speed" target="_blank">The True Cost of Speed: What Query Performance Really Costs at Scale</a> - 3rd February
* <a href="https://luma.com/j2ck1sbz" target="_blank">AI Night SF</a> - 11th February
* <a href="https://www.meetup.com/clickhouse-toronto-user-group/events/312881151/?slug=clickhouse-toronto-user-group&eventId=310164482&isFirstPublish=true" target="_blank">Toronto Meetup</a> - 19th February
* <a href="https://luma.com/jsctpwoa" target="_blank">Seattle Meetup</a> - 26th February
* <a href="https://luma.com/wbkqmaqk" target="_blank">LA Meetup</a> - 6th March

### Events in EMEA

* <a href="https://luma.com/3szhmv9h" target="_blank">Data & AI Paris Meetup</a> - 22nd January
* <a href="https://clickhouse.com/company/events/agentic-data-stack-ams" target="_blank">The Agentic Data Stack: The Future is Conversational</a> (Amsterdam) - 27th January
* <a href="https://clickhouse.com/company/events/202601-EMEA-Paris-meetup" target="_blank">ClickHouse Meetup in Paris</a> - 28th January
* <a href="https://luma.com/yx3lhqu9" target="_blank">Apache Iceberg™ Meetup Belgium: FOSDEM Edition</a> - 30th January
* <a href="https://luma.com/czvs584m" target="_blank">FOSDEM Community Dinner Brussels</a> - 31st January
* <a href="https://clickhouse.com/company/events/202602-EMEA-Barcelona-meetup" target="_blank">ClickHouse Meetup in Barcelona</a> - 5th February
* <a href="https://clickhouse.com/company/events/202602-EMEA-London-meetup" target="_blank">ClickHouse Meetup in London</a> - 10th February
* <a href="https://www.meetup.com/clickhouse-georgia-meetup-group/events/312852206/" target="_blank">ClickHouse Meetup in Tbilisi Georgia</a> - 24th February

### Events in APAC

* <a href="https://clickhouse.com/company/events/202601-APJ-Singapore-Meetup" target="_blank">ClickHouse Singapore Meetup</a> - 27th January
* <a href="https://clickhouse.com/company/events/202601-APJ-Real-time-Analytics-w-ClickHouse" target="_blank">Boot Camp: Real-time Analytics with ClickHouse</a> - 27th January
* <a href="https://clickhouse.com/company/events/202601-apj-seoul-meetup" target="_blank">ClickHouse Seoul Meetup</a> - 29th January

### Speaking at ClickHouse meetups

Want to speak at a ClickHouse meetup? <a href="https://docs.google.com/forms/d/e/1FAIpQLSdpYbh0k3hmLOQ7JLXrubvEbiIul4TxJDp1AVewXHSdzHcmzA/viewform" target="_blank">Apply here!</a>

Below are some upcoming call for papers (CFPs):

* <a href="https://sessionize.com/iceberg-summit-2026/" target="_blank">Iceberg Summit SF</a> - April 6-8
* <a href="https://aicouncil.com/apply-to-speak" target="_blank">AI Council SF</a> - May 12-14
* <a href="https://sessionize.com/observability-summit-2026" target="_blank">Observability Summit Minneapolis</a>  - May 21-22
* <a href="https://events.linuxfoundation.org/kubecon-cloudnativecon-india/program/cfp/" target="_blank">Kubecon India Mumbai</a> - June 18-19
* <a href="https://pretalx.com/grafanacon-2026/cfp" target="_blank">GrafanaCon Barcelona</a> - April 20-22
* <a href="https://sessionize.com/wearedevelopers-world-congress-2026-europe" target="_blank">We Are Developers Berlin</a> - July 8-10


Welcome to the January 2026 ClickHouse newsletter, which will round up what’s happened in real-time data warehouses over the last month.

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January 2026 newsletter

Over 100 functions were added to ClickHouse in 2025. These were some of my favorites.

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New functions you might have missed in 2025

Hello, and welcome to the December 2025 ClickHouse newsletter!

This month, we have a Postgres extension for querying ClickHouse, an analysis of how the five major cloud data warehouses compare in terms of cost-performance, a review of the year in Postgres CDC, and more!

## Featured community member: Zjan Carlo Turla {#featured-community-member}

This month's featured community member is Zjan Carlo Turla, Software Engineer at Canva.

![dec2025_image3.png](/uploads/dec2025_image3_5c148fc70e.png)

Zjan works on Canva's Observability team, where he builds and maintains systems that monitor and ensure reliability across Canva's distributed infrastructure. Previously, he worked as a DevOps Consultant supporting large-scale platforms and spent several years at Kalibrr as an SRE, migrating monolithic applications to microservices on Kubernetes.

At the recent <a href="https://clickhouse.com/openhouse/sydney" target="_blank">Open House roadshow in Sydney</a>, he shared <a href="https://clickhouse.com/blog/canva-faster-search-lower-costs" target="_blank">how Canva migrated production observability workloads in ClickHouse</a>, processing 3 million spans and 3 million logs per second for 240 million monthly active users, achieving 10x faster search and 70% cost savings.

➡️ <a href="https://www.linkedin.com/in/zjan-carlo-turla-358b28164/" target="_blank">Connect with Zjan</a>

## Upcoming events {#upcoming-events}

### Global virtual events

* <a href="https://clickhouse.com/company/events/v25-12-community-release-call" target="_blank">v25.12 Community Call</a> - December 18

### Virtual training

* <a href="https://clickhouse.com/company/events/202512-amer-clickhouse-certified-developer-exam" target="_blank">Preparing for the ClickHouse Certified Developer Exam</a> - December 18

**Real-time Analytics**

* <a href="https://clickhouse.com/company/events/202601-EMEA-Real-time-Analytics-with-ClickHouse-Level1" target="_blank">Real-time Analytics with ClickHouse: Level 1</a> - January 14
* <a href="https://clickhouse.com/company/events/202601-EMEA-Real-time-Analytics-with-ClickHouse-Level2" target="_blank">Real-time Analytics with ClickHouse: Level 2</a> - January 21
* <a href="https://clickhouse.com/company/events/202601-EMEA-Real-time-Analytics-with-ClickHouse-Level3" target="_blank">Real-time Analytics with ClickHouse: Level 3</a> - January 28

**Observability**

* <a href="https://clickhouse.com/company/events/202512-AMER-Observability-with-ClickStack" target="_blank">Observability with ClickStack: Level 2</a> - December 17
* <a href="https://clickhouse.com/company/events/202602-AMER-Observability-with-ClickStack-Level1" target="_blank">Observability with ClickStack: Level 1</a> - February 4

### Events in AMER

* <a href="https://luma.com/abggijbh" target="_blank">Iceberg Meetup in Menlo Park</a> - January 21st
* <a href="https://luma.com/ifxnj82q" target="_blank">Iceberg Meetup in NYC</a> - January 23rd
* <a href="https://luma.com/iicnlq41" target="_blank">New York Meetup</a> - January 26th

### Events in EMEA

* <a href="https://clickhouse.com/company/events/202512-EMEA-TelAviv-meetup" target="_blank">ClickHouse Meetup in Tel Aviv</a> - December 29
* <a href="https://luma.com/3szhmv9h" target="_blank">Data & AI Paris Meetup</a> - January 22nd
* <a href="https://luma.com/yx3lhqu9" target="_blank">Apache Iceberg™ Meetup Belgium: FOSDEM Edition</a> - January 30th

### Events in APAC

* <a href="https://clickhouse.com/company/events/202601-APJ-Webinar-Materialized-Views" target="_blank">Under-the-Hood: Incremental Materialized Views & Dictionaries Webinar</a> - January 15

## Our gift to you: Free ClickHouse certification and new learning paths {#gift}

We've launched all-new self-paced learning paths designed to deliver the hands-on experience needed to build real-world skills and expertise to match your goals. Explore our new paths today:

* <a href="https://clickhouse.com/learn/real-time-analytics" target="_blank">Real-time Analytics with ClickHouse</a> - Learn how to power real-time dashboards, alerts, and event-driven apps with ClickHouse.
* <a href="https://clickhouse.com/learn/observability" target="_blank">Observability with ClickStack</a> - Ingest logs, metrics, and traces to monitor systems and power observability dashboards.
* <a href="https://learn.clickhouse.com/class_catalog/category/141050" target="_blank">Machine Learning and GenAI with ClickHouse</a> - Use ClickHouse to prepare data, feed models, and support GenAI workflows at scale.
* Data Warehousing with ClickHouse - Coming Soon! Design, build, and optimize modern data warehouses using ClickHouse.

As our holiday gift, get certified for free through the end of 2025. Use code **2025CERTFREE** at checkout to claim your certification at no cost.

➡️ <a href="https://clickhouse.com/learn" target="_blank">Start learning</a>

## 25.11 release {#release}

![dec2025_image9.png](/uploads/dec2025_image9_d03fe17462.png)

My favourite feature in our penultimate release of the year, 25.11, is projections as secondary indices, which lets you create lightweight projections that behave like a secondary index without duplicating complete rows of data.

This release also features faster GROUP BY operations on 8-bit and 16-bit integer keys, as well as the argAndMin and argAndMax functions, fractional LIMIT and OFFSET, and more.

➡️ <a href="https://clickhouse.com/blog/clickhouse-release-25-11" target="_blank">Read the release post</a>

## Introducing pg_clickhouse: A Postgres extension for querying ClickHouse {#pg_clickhouse}

![dec2025_image8.png](/uploads/dec2025_image8_030a51e094.png)

David Wheeler announced the release of pg_clickhouse, a PostgreSQL extension that brings ClickHouse's analytical power directly into your Postgres queries through foreign data wrappers.

Query ClickHouse tables from Postgres with intelligent pushdown optimization that executes aggregations and filters in ClickHouse for maximum performance, giving you access to massive analytical datasets without leaving your Postgres environment.

➡️ <a href="https://clickhouse.com/blog/introducing-pg_clickhouse" target="_blank">Read the announcement</a>

## Dlt+ClickHouse+Rill: Multi-Cloud Cost Analytics, Cloud-Ready {#dlt_clickhouse_rill}

![dec2025_image6.png](/uploads/dec2025_image6_919ef77e95.png)

Simon Späti demonstrates how to build a real-time FinOps dashboard using dlt to ingest AWS cost and usage reports into ClickHouse, and then visualizes the data with Rill.

The setup provides a practical blueprint for instant cost analysis at scale, with ClickHouse serving as the analytical engine to handle millions of cost records.

➡️ <a href="https://www.ssp.sh/blog/finops-dlt-clickhouse-rill/" target="_blank">Read the blog post</a>

## Postgres CDC in ClickHouse, A year in review {#postgres_cdc_clickhouse}

![dec2025_image2.png](/uploads/dec2025_image2_b6a73bb304.png)

Sai Srirampur reflects on a year of building Postgres CDC in ClickHouse Cloud, growing from a handful of PeerDB users to over 400 companies replicating more than 200 TB of data monthly.

The post highlights technical wins, such as eliminating expensive replication reconnects that caused hours of lag and reducing partition generation from over 7 hours to under a second, while outlining next steps to close data modeling gaps and further scale logical replication.

➡️ <a href="https://clickhouse.com/blog/postgres-cdc-year-in-review-2025" target="_blank">Read the blog post</a>

## ClickHouse as a security engine: Tempesta FW's approach to L7 DDoS and bot mitigation {#clickhouse_security_engine}

![dec2025_image4.jpg](/uploads/dec2025_image4_f0455307df.jpg)

Tempesta Technologies developed WebShield, an open-source bot detection system that utilizes ClickHouse to analyze access logs in real-time and automatically block Layer 7 DDoS attacks and malicious bots.

➡️ <a href="https://tempesta-tech.com/blog/defending-against-l7-ddos-and-web-bots-with-tempesta-fw/" target="_blank">Read the blog post</a>

## How the five major cloud data warehouses compare on cost-performance {#cloud_data_warehouses_cost_performance}

![dec2025_image1.png](/uploads/dec2025_image1_a877836355.png)

Did you know that public price lists of cloud data warehouses don't tell you real costs? Much more important is the amount of computing power the underlying engine consumes to run your queries.

Tom Schreiber & Lionel Palacin break down <a href="https://clickhouse.com/blog/how-cloud-data-warehouses-bill-you" target="_blank">how Snowflake, BigQuery, Databricks, and Redshift bill you</a>, then benchmark their actual cost-performance against ClickHouse.

➡️ <a href="https://clickhouse.com/blog/cloud-data-warehouses-cost-performance-comparison" target="_blank">Read the blog post</a>

## clickhouse.build: An agentic CLI to accelerate Postgres apps with ClickHouse {#clickhouse_build}

![dec2025_image7.png](/uploads/dec2025_image7_7e52ce635d.png)

A Postgres + ClickHouse proof of concept in an hour? It sounds too good to be true, but clickhouse.build does precisely that.

Our new open-source CLI uses agents to scan your TypeScript code, identify analytical queries, configure ClickPipes CDC, and rewrite your app to use both databases - with a feature flag to toggle between backends and measure the impact.

➡️ <a href="https://clickhouse.com/blog/clickhouse-build-agentic-cli-accelerate-postgres-clickhouse-apps" target="_blank">Read the blog post</a>

## Quick reads {#quick-reads}

* Ahmet Kürşat Şerolar <a href="https://medium.com/logalarm-devs/clickhouse-fine-tuning-maximize-performance-for-time-series-and-logs-5b6f6943ca7c" target="_blank">shares a deep-dive on optimizing ClickHouse</a> for logs and time-series data, covering engine selection, partitioning, LowCardinality fields, codecs (DoubleDelta + ZSTD), materialized views, and TTL-based storage tiers.
* Vignesh T K <a href="https://www.mafiree.com/readBlog/speeding-up-clickhouse-queries-materialized-views-vs-refreshable-views-explained" target="_blank">explains the difference</a> between ClickHouse's Materialized Views (real-time updates on insert, best for streaming data) and Refreshable Materialized Views (scheduled periodic updates, better for complex joins and batch analytics).
* Georgii Baturin walks through <a href="https://medium.com/hands-on-dbt-with-clickhouse/hands-on-dbt-with-clickhouse-1-local-sandbox-and-safe-training-data-64f897be6843" target="_blank">setting up a local dbt analytics environment with ClickHouse</a>, covering Docker setup, creating separate training databases for raw data and dbt models, connecting dbt-core with the ClickHouse adapter, and configuring Git - providing a practical sandbox for learning dbt without touching production systems.
* Thinh Dang provides <a href="https://thinhdanggroup.github.io/tables-distributed-clickhouse-cluster/" target="_blank">a comprehensive guide to creating tables in distributed ClickHouse clusters</a>, covering local vs Distributed tables, ReplicatedMergeTree with Keeper coordination, ON CLUSTER DDL, sharding keys, internal_replication settings, and operational patterns like materialized views for aggregations - plus a practical checklist to avoid schema inconsistencies and replication headaches.
* Paul Bardea explains <a href="https://www.blacksmith.sh/blog/logging" target="_blank">how Blacksmith built a logging platform for GitHub Actions with ClickHouse</a>.



Welcome to the December 2025 ClickHouse newsletter, which will round up what’s happened in real-time data warehouses over the last month.

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December 2025 newsletter

Hello, and welcome to the November 2025 ClickHouse newsletter!

This month, we have big news with our LibreChat acquisition, a data analyst's AI-powered warehouse build, 170x log compression techniques, and auto-exporting traces to OpenTelemetry.

## Featured community member: Kiyose Ryu  {#featured-community-member}

This month's featured community member is Kiyose Ryu, Engineering Manager at Smartnews, Inc.

![nov2025_image1.png](https://cms.clickhouse-dev.com:1337/uploads/nov2025_image1_44b9d11f45.png)

Kiyose Ryu has worked at Smartnews for the past five years, where he's helped build a real-time aggregation system using ClickHouse.

Smartnews began introducing ClickHouse in 2020, and by 2021, had converted all advertiser reports to real-time. Advertisers need up-to-the-minute data to manage their campaigns effectively, which is why Smartnews prioritized delivering accurate, real-time reports. Kiyose Ryu <a href="https://clickhouse.com/videos/tokyo-meetup-smartnews-15apr25" target="_blank">shared the details of their implementation at the ClickHouse Tokyo meetup</a>.

➡️ <a href="https://about.smartnews.com/ja/" target="_blank">Learn more about Smartnews</a>

## Upcoming events {#upcoming-events}

### Global virtual events

* <a href="https://clickhouse.com/company/events/webinar-f45-fiveonefour-clickhouse" target="_blank">How F45 Turns 1B+ Data Points into 70% Higher Member Satisfaction</a> - November 20
* <a href="https://clickhouse.com/company/events/v25-11-community-release-call" target="_blank">v25.11 Community Call</a> - November 25

### Virtual training

**Real-time Analytics**

* <a href="https://clickhouse.com/company/events/202511-AMER-Real-time-Analytics-with-ClickHouse-Level1" target="_blank">Real-time Analytics with ClickHouse: Level 1</a> - November 19
* <a href="https://clickhouse.com/company/events/202511-APJ-Real-time-Analytics-with-ClickHouse-Level1" target="_blank">Real-time Analytics with ClickHouse: Level 1</a> (APJ-friendly) - November 25
* <a href="https://clickhouse.com/company/events/202511-APJ-Real-time-Analytics-with-ClickHouse-Level2" target="_blank">Real-time Analytics with ClickHouse: Level 2</a> (APJ-friendly) - November 26
* <a href="https://clickhouse.com/company/events/202511-APJ-Real-time-Analytics-with-ClickHouse-Level3" target="_blank">Real-time Analytics with ClickHouse: Level 3</a> (APJ-friendly) - November 27
* <a href="https://clickhouse.com/company/events/202512-AMER-Real-time-Analytics-with-ClickHouse-Level1" target="_blank">Real-time Analytics with ClickHouse: Level 1</a> - December 2
* <a href="https://clickhouse.com/company/events/202512-AMER-Real-time-Analytics-with-ClickHouse-Level2" target="_blank">Real-time Analytics with ClickHouse: Level 2</a> - December 3
* <a href="https://clickhouse.com/company/events/202512-AMER-Real-time-Analytics-with-ClickHouse-Level3" target="_blank">Real-time Analytics with ClickHouse: Level 3</a> - December 4
* <a href="https://clickhouse.com/company/events/202512-AMER-Real-time-Analytics-with-ClickHouse-Level1" target="_blank">Real-time Analytics with ClickHouse: Level 1</a> - December 9
* <a href="https://clickhouse.com/company/events/202512-AMER-Real-time-Analytics-with-ClickHouse-Level2" target="_blank">Real-time Analytics with ClickHouse: Level 2</a> - December 10
* <a href="https://clickhouse.com/company/events/202512-AMER-Real-time-Analytics-with-ClickHouse-Level3" target="_blank">Real-time Analytics with ClickHouse: Level 3</a> - December 11

**Observability**

* <a href="https://clickhouse.com/company/events/202511-EMEA-Observability-at-Scale-with-ClickStack" target="_blank">Observability at Scale with ClickStack</a> - November 26
* <a href="https://clickhouse.com/company/events/202512-AMER-Observability-at-Scale-with-ClickStack" target="_blank">Observability at Scale with ClickStack</a> - December 3
* <a href="https://clickhouse.com/company/events/202512-AMER-Observability-with-ClickStack" target="_blank">Observability with ClickStack: Level 2</a> - December 17

### Events in AMER

* <a href="https://clickhouse.com/houseparty/the-sql" target="_blank">House Party, The SQL</a>, Las Vegas - December 3

### Events in EMEA

* <a href="https://www.forward-data-conference.com/en" target="_blank">ForwardData Paris (Data&AI)</a> - November 24
* <a href="https://www.be4data.com/" target="_blank">Paris Monitoring Day</a> - November 25
* <a href="https://www.meetup.com/clickhouse-poland-user-group/events/311309076/?eventOrigin=network_page" target="_blank">ClickHouse Meetup Warsaw</a> - November 26
* <a href="https://clickhouse.com/company/events/202512-EMEA-TelAviv-meetup" target="_blank">ClickHouse Meetup in Tel Aviv</a> - December 29

### Events in APAC

* <a href="https://clickhouse.com/company/events/202511-in-person-Mumbai-Real-time-Analytics-with-ClickHouse-Level1" target="_blank">Mumbai In-Person Training - Real-time Analytics with ClickHouse: Level 1</a> - November 21
* <a href="https://www.meetup.com/clickhouse-thailand-meetup-group/events/311852739/" target="_blank">ClickHouse + AWS Bangkok Meetup</a> - November 25
* <a href="https://clickhouse.com/company/events/2025-12-APJ-Tokyo-OpenSourceSummitJapan" target="_blank">Open Source Summit Japan</a> - December 8
* <a href="https://clickhouse.com/company/events/202512-in-person-Jakarta-Real-time-Analytics-with-ClickHouse-Level1" target="_blank">Jakarta In-Person Training - Real-time Analytics with ClickHouse: Level 1</a> - December 9
* <a href="https://www.meetup.com/clickhouse-indonesia-user-group/events/311988089/" target="_blank">ClickHouse Jakarta Meetup</a> - December 9
* <a href="https://www.meetup.com/clickhouse-tokyo-user-group/events/311974739/" target="_blank">ClickHouse Tokyo Meetup & Year-End Party</a> - December 15
* <a href="https://clickhouse.com/company/events/2025-12-APJ-Tokyo-AIEngineeringSummitJapan" target="_blank">AI Engineering Summit Tokyo</a> - December 16

## 25.10 release {#release}

![nov2025_image2.png](https://cms.clickhouse-dev.com:1337/uploads/nov2025_image2_d724343f36.png)

ClickHouse 25.10 sees a collection of JOIN performance optimizations. These include lazy column replication, bloom filter optimizations, and smarter push-down of complex conditions, delivering up to 24 times faster queries in some cases.

There are also several additions to the SQL syntax, including the `<=>` (IS NOT DISTINCT FROM) operator, negative limit and offset (perfect for getting the n most recent records but returning them in ascending order), and `LIMIT BY ALL`.

And finally, my personal favorite - as of ClickHouse 25.10, we can query the ClickHouse Arrow Flight server using the ClickHouse Arrow Flight client.

➡️ <a href="https://clickhouse.com/blog/clickhouse-release-25-10" target="_blank">Read the release post</a>

## ClickHouse welcomes LibreChat: Introducing the open-source Agentic Data Stack {#librechat}

![nov2025_image3.png](https://cms.clickhouse-dev.com:1337/uploads/nov2025_image3_cdd181698e.png)

We acquired LibreChat, the leading open-source AI chat platform, to create the "Agentic Data Stack" - combining LibreChat's multi-LLM interface with ClickHouse's analytical speed so users can query data in plain English.

Companies like Shopify, Daimler Truck, and cBioPortal are already using this stack to democratize data access, and <a href="https://clickhouse.com/blog/ai-first-data-warehouse" target="_blank">our own AI-powered data warehouse</a> now handles 70% of queries for 200+ users.

LibreChat remains 100% open-source under its MIT license, and we plan to implement deeper native integrations while preserving the platform's flexibility.

➡️ <a href="https://clickhouse.com/blog/librechat-open-source-agentic-data-stack" target="_blank">Read the announcement</a>

## Streaming asynchronous inserts monitoring in ClickHouse {#streaming-asynchronous-inserts-monitoring-in-clickhouse}

![nov2025_image4.png](https://cms.clickhouse-dev.com:1337/uploads/nov2025_image4_bcbf17b7d3.png)

AB Tasty's William Attache explains how his team built a comprehensive monitoring system to track ClickHouse asynchronous inserts end-to-end, from initial requests through flush queries to final part merges. The team created a custom view that joins data from multiple system tables to visualize the complete lifecycle of streaming inserts.

Along the way, they achieved significant cost savings by switching from JSON to RowBinary format and optimizing their batch sizes based on how ClickHouse actually creates and merges parts.

➡️ <a href="https://medium.com/the-ab-tasty-tech-blog/streaming-asynchronous-inserts-monitoring-in-clickhouse-c1378bd8b159" target="_blank">Read the blog post</a>

## We built a vector search engine that lets you choose precision at query time {#we-built-a-vector-search-engine-that-lets-you-choose-precision-at-query-time}

![nov2025_image5.png](https://cms.clickhouse-dev.com:1337/uploads/nov2025_image5_178fcf89ba.png)

Raufs Dunamalijevs added QBit to ClickHouse, a column type that stores floats as bit planes. It allows you to choose how many bits to read during vector search, thereby tuning recall and performance without altering the data.

➡️ <a href="https://clickhouse.com/blog/qbit-vector-search" target="_blank">Read the blog post</a>

## From 0–1: Building our data warehouse with ClickHouse to enable self-serve analytics and observability at scale {#from-0-1-building-our-data-warehouse-with-clickhouse-to-enable-self-serve-analytics-and-observability-at-scale}

![nov2025_image6.png](https://cms.clickhouse-dev.com:1337/uploads/nov2025_image6_ea0a2450fb.png)

Viralo hit 10M users, and their PostgreSQL analytics setup collapsed, with dashboards taking over 30 minutes to load, CPUs maxing out at over 80%, and queries failing. They migrated to ClickHouse Cloud and implemented a <a href="https://clickhouse.com/blog/building-a-medallion-architecture-with-clickhouse" target="_blank">medallion architecture</a>, using SQL for all data transformations instead of external ETL tools, which reduced query time to under 30 seconds.

Notably, Shubham Bhardwaj's team constructed the entire warehouse using a low-code approach, leveraging Claude Sonnet for code assistance, thereby eliminating orchestration tool costs and demonstrating that innovative architecture and AI tooling can effectively replace complex data stacks.

➡️ <a href="https://medium.com/@shubhamb957/from-0-1-building-our-data-warehouse-with-clickhouse-to-enable-self-serve-analytics-and-f5fbe2cd7e3a" target="_blank">Read the blog post</a>

## Tracing the invisible: Building end-to-end observability in a real-time streaming pipeline {#tracing-the-invisible-building-end-to-end-observability-in-a-real-time-streaming-pipeline}

![nov2025_image7.png](https://cms.clickhouse-dev.com:1337/uploads/nov2025_image7_919adb86b2.png)

When building end-to-end observability for their real-time metrics pipeline, Pranav Mehta's team faced a unique challenge: ClickHouse stores query spans internally, but it cannot use an SDK to push those traces to an OpenTelemetry collector, as is done with application services.

They came up with a clever idea of using an incremental materialized view that writes to a table backed by the URL engine, which points at the OTel collector API.

Now they can trace a request all the way from the application, through NATS JetStream, into ClickHouse query execution - and see it all in one view.

➡️ <a href="https://medium.com/@pranavmehta94/tracing-the-invisible-building-end-to-end-observability-in-a-real-time-streaming-pipeline-eccc91524e24" target="_blank">Read the blog post</a>

## ClickHouse partners with Japan Cloud to establish ClickHouse K.K. and accelerate growth in Japan {#clickhouse-partners-with-japan-cloud-to-establish-clickhouse-k-k-and-accelerate-growth-in-japan}

![nov2025_image8.png](https://cms.clickhouse-dev.com:1337/uploads/nov2025_image8_c644ce69a0.png)

Earlier this month, ClickHouse announced the establishment of ClickHouse K.K., its Japanese subsidiary, through a strategic partnership with Japan Cloud.

➡️ <a href="https://clickhouse.com/blog/japan-cloud" target="_blank">Read the blog post</a>

## Quick reads {#quick-reads}

* Alexey Milovidov <a href="https://clickhouse.com/blog/planes-weather" target="_blank">derives and visualizes real-time weather data</a> (wind direction, speed, and air pressure) from airplane telemetry stored in ClickHouse using trigonometry and color mapping.
* Nisarg Pipaliy has written <a href="https://medium.com/@nisargpipaliya2402/clickhouse-explained-simply-why-its-different-and-when-to-use-it-9b298406485d" target="_blank">a beginner-friendly explainer that breaks down ClickHouse's table engines</a>, showing how different engines, such as MergeTree, ReplacingMergeTree, and SummingMergeTree, give tables distinct "personalities" for handling deduplication, aggregation, and replication. This makes it clear why ClickHouse is fundamentally different from traditional row-based databases, such as PostgreSQL.
* Julian Virguez <a href="https://medium.com/@julianvirguez/real-time-product-sentiment-wiring-clickhouse-data-into-sf-ui-557812267d29" target="_blank">wired ClickHouse directly into Salesforce</a> using a Lightning Web Component that queries 150M rows of Amazon review data in under a second.
* Lionel Palacin demonstrated <a href="https://clickhouse.com/blog/log-compression-170x" target="_blank">how to achieve 170x+ compression on Nginx logs</a> by transforming raw text into structured columns with optimized data types and strategic ordering keys. He then followed this up with another post showing how to <a href="https://clickhouse.com/blog/improve-compression-log-clustering" target="_blank">automatically group similar log messages and extract variable fields into columns</a>, achieving nearly 50x compression while keeping logs fully queryable and reconstructable.
* Andrii K walks through <a href="https://medium.com/@andriikrymus/streaming-postgresql-data-changes-to-clickhouse-with-debezium-kafka-18dbebb8f29a" target="_blank">setting up a complete CDC pipeline</a> using Debezium to capture PostgreSQL changes, stream them through Kafka with Avro serialization, and sink into ClickHouse.

## Video corner {#video-corner}

* Mark Needham demonstrates the <a href="https://clickhouse.com/videos/mcp-server-chdb" target="_blank">ClickHouse MCP server's new chDB mode</a>, which enables in-process execution of ClickHouse queries without a server.
* At Web Summit 2025, <a href="https://clickhouse.com/videos/web-summit-2025-alexey-milovidov" target="_blank">Alexey Milovidov demonstrated loading massive public datasets into ClickHouse and then running real-time analytics</a>, such as comparing writing styles across domains, tracking trends on Reddit, and creating an interactive map that showed the "best photo" for every location on Earth.
* At <a href="https://clickhouse.com/openhouse/bangalore" target="_blank">OpenHouse Bangalore 2025</a>, Kiran Raparti and Pragnesh Bhavsar from HighLevel explained how they <a href="https://clickhouse.com/videos/open-house-bangalore-highlevel" target="_blank">migrated four critical use cases from MySQL, Elasticsearch, and MongoDB to ClickHouse</a>.


Welcome to the November 2025 ClickHouse newsletter, which will round up what’s happened in real-time data warehouses over the last month.

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November 2025 newsletter

A walkthrough showing how to trace an OpenAI agents app.

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Tracing OpenAI agents with ClickStack

Hello, and welcome to the October 2025 ClickHouse newsletter!

This month, we have a new text index, scaling request logging from millions to billions, modeling messy data for OLAP, querying lakehouses from ClickHouse Cloud, and more!

## Featured community member: Mayank Joshi

This month's featured community member is Mayank Joshi, Co-Founder and CTO at Auditzy.

![image6.png](/uploads/image6_15dde934cf.png)

Auditzy is a SaaS platform that provides comprehensive website auditing for performance, SEO, accessibility, and security analysis. Since 2022, they have been developing tools that provide technical insights to both technical and non-technical users, enabling teams to monitor website health and make data-driven improvements.

When scaling Auditzy's data processing capabilities, they migrated from PostgreSQL to ClickHouse, achieving a 33x performance improvement. Mayank shared this migration story at a ClickHouse meetup in Mumbai in July 2025, and it was <a href="https://clickhouse.com/blog/auditzy-33x-faster-clickhouse-vs-postgres" target="_blank">written up in blog post for the ClickHouse community</a>, highlighting the challenges with Postgres and the benefits of ClickHouse's ultra-fast, scalable architecture.

➡️ <a href="https://www.linkedin.com/in/themayankjoshi/" target="_blank">Follow Mayank on LinkedIn</a>

## Upcoming events

### Open House Roadshow

We have one more event left on the Open House Roadshow, and it’s in our home city of Amsterdam on 28th October!

The event will include keynotes, deep-dive talks, live demos, and AMAs with ClickHouse creators, builders, and users, as well as the opportunity to network with the ClickHouse community.

Alexey Milovidov (our CTO), Tyler Hannan (Senior Director of Developer Relations), and members of our engineering team will be there, so come say hi!

➡️ <a href="https://clickhouse.com/company/events/202510-amsterdam-open-house" target="_blank">Register for the Amsterdam User Conference on October 28</a>

### Global events

* <a href="https://clickhouse.com/company/events/v25-10-community-release-call" target="_blank">v25.10 Community Call</a> - October 30
* <a href="https://clickhouse.com/company/events/202510-EMEA-Webinar-ClickStack-French" target="_blank">Moderniser l’observabilité avec ClickStack : simplifier, accélérer, innover</a> - October 29
* <a href="https://clickhouse.com/company/events/202510-EMEA-Webinar-Iceberg-German" target="_blank">Next Gen Lakehouse Stack: ClickHouse Performance, Iceberg Catalog & Governance</a> - October 29
* <a href="https://clickhouse.com/company/events/202511-intro-clickstack-amer" target="_blank">Introducing ClickStack: The Future of Observability on ClickHouse</a> - November 4

### Virtual training

* <a href="https://clickhouse.com/company/events/202510-AMER-Real-time-Analytics-with-ClickHouse-Level1" target="_blank">Real-time Analytics with ClickHouse: Level 1</a> - October 28
* <a href="https://clickhouse.com/company/events/202510-AMER-Real-time-Analytics-with-ClickHouse-Level2" target="_blank">Real-time Analytics with ClickHouse: Level 2</a> - October 30
* <a href="https://clickhouse.com/company/events/202510-AMER-Real-time-Analytics-with-ClickHouse-Level3" target="_blank">Real-time Analytics with ClickHouse: Level 3</a> - October 31
* <a href="https://clickhouse.com/company/events/202511-amer-emea-query-optimization" target="_blank">ClickHouse Query Optimization Workshop</a> - November 5
* <a href="https://clickhouse.com/company/events/202511-AMER-chDB:Data-Analytics-with-ClickHouse-and-Python" target="_blank">chDB: Data Analytics with ClickHouse and Python</a> - November 12
* <a href="https://clickhouse.com/company/events/202511-AMER-Real-time-Analytics-with-ClickHouse-Level1" target="_blank">Real-time Analytics with ClickHouse: Level 1</a> - November 19
* <a href="https://clickhouse.com/company/events/202512-AMER-Real-time-Analytics-with-ClickHouse-Level1" target="_blank">Real-time Analytics with ClickHouse: Level 1</a> - December 2
* <a href="https://clickhouse.com/company/events/202512-AMER-Real-time-Analytics-with-ClickHouse-Level2" target="_blank">Real-time Analytics with ClickHouse: Level 2</a> - December 3
* <a href="https://clickhouse.com/company/events/202512-AMER-Real-time-Analytics-with-ClickHouse-Level3" target="_blank">Real-time Analytics with ClickHouse: Level 3</a> - December 4
* <a href="https://clickhouse.com/company/events/202512-AMER-Observability-at-Scale-with-ClickStack" target="_blank">Observability at Scale with ClickStack</a> - December 10

### Events in AMER

* <a href="https://clickhouse.com/company/events/202509-amer-bo-meetup" target="_blank">Boston ClickHouse Meetup</a> - September 19
* <a href="https://clickhouse.com/company/events/202511-LATAM-Real-time-Analytics-with-ClickHouse" target="_blank">In person training: Real-time Analytics with ClickHouse, Sao Paolo</a> - November 4
* <a href="https://clickhouse.com/company/events/202511-in-person-Atlanta-Observability-at-Scale-ClickStack" target="_blank">Atlanta In-Person Training - Observability at Scale with ClickStack</a> - November 10
* <a href="https://clickhouse.com/houseparty/the-sql" target="_blank">House Party, The SQL</a>, Las Vegas - December 2

### Events in EMEA

* <a href="https://clickhouse.com/company/events/202510-amsterdam-open-house" target="_blank">Amsterdam User Conference</a> - October 28
* <a href="https://clickhouse.com/company/events/202510-in-person-clickhouse-deep-dive-part-1" target="_blank">ClickHouse Deep Dive Part 1 In-Person Training</a> (Amsterdam) - October 28
* <a href="https://www.techshowmadrid.es/en/big-data-ai-world" target="_blank">BigData & AI World Madrid</a>  - October 29-30
* <a href="https://luma.com/event/manage/evt-iaVxW6AdEaFzKSD" target="_blank">AI Night Tallinn by ClickHouse</a> - October 30
* <a href="https://www.gartner.com/en/conferences/emea/symposium-spain" target="_blank">Gartner IT Barcelona</a> - November 10-13
* <a href="https://www.forward-data-conference.com/en" target="_blank">ForwardData Paris (Data&AI)</a> - November 24
* <a href="https://www.be4data.com/" target="_blank">Paris Monitoring Day</a> - November 25
* <a href="https://www.meetup.com/clickhouse-poland-user-group/events/311309076/?eventOrigin=network_page" target="_blank">ClickHouse Meetup Warsaw</a> - November 26

### Events in APAC

* <a href="https://vdac.vn/pages/indonesia-30-october-2025" target="_blank">Data & AI Summit Indonesia</a> - October 30
* <a href="https://www.getdbt.com/events/roadshow/coalesce-in-sydney" target="_blank">Coalesce Sydney</a> - November 6
* <a href="https://www.getdbt.com/events/roadshow/coalesce-in-melbourne" target="_blank">Coalesce Melbourne</a> - November 11
* <a href="https://laracon.au/" target="_blank">Laracon.au</a> - 13-14 November

## 25.9 release

![image7.png](/uploads/image7_ec1f65c362.png)

My favorite feature in ClickHouse 25.9 is the completely redesigned text index. The new architecture diverges from the previous FST-based implementation to a streaming-friendly design structured around skip index granules, thereby enhancing query analysis efficiency and eliminating the need to load large chunks of data into memory.

The release also introduces automatic global join reordering, achieving 1,450x speedups in TPC-H benchmarks, as well as streaming secondary indices that eliminate startup delays and expanded data lake support, including enhancements to Apache Iceberg.

➡️ <a href="https://clickhouse.com/blog/clickhouse-release-25-09" target="_blank">Read the release post</a>

## Scaling request logging from millions to billions with ClickHouse, Kafka, and Vector

![image8.png](/uploads/image8_22f491bb62.png)

Geocodio migrated from MariaDB to ClickHouse to handle billions of monthly geocoding requests after their deprecated TokuDB engine could no longer keep up with the scale, according to TJ Miller's detailed technical post. The initial approach encountered a common ClickHouse newcomer issue - direct row-level inserts resulted in a `TOO_MANY_PARTS` error, as the system couldn't merge parts quickly enough.

After consulting with the Honeybadger team (who had successfully implemented ClickHouse for their own analytics platform), Miller learned that ClickHouse's key requirement was the batch processing of records. The final architecture uses Kafka and Vector to aggregate data before inserting it into ClickHouse Cloud, with feature flags enabling a zero-downtime migration by running both systems in parallel for validation.

➡️ <a href="https://www.geocod.io/code-and-coordinates/2025-10-02-from-millions-to-billions/" target="_blank">Read the blog post</a>

## If it’s in your catalog, you can query it: The DataLakeCatalog engine in ClickHouse Cloud

![image5.png](/uploads/image5_c5942ed537.png)

Tom Schreiber's guide highlights how ClickHouse Cloud now offers managed DataLakeCatalog functionality, bringing lakehouse capabilities to the cloud service with integrated AWS Glue and Databricks Unity Catalog support in beta.

The Cloud service eliminates the operational complexity of self-managing catalog integrations while leveraging the same high-performance execution path that handles MergeTree, Iceberg, and Delta Lake data uniformly. It also automatically discovers and queries Iceberg and Delta Lake tables from catalog metadata, supporting full Iceberg v2 features and complete Delta Lake compatibility.

Built on recent improvements, including rebuilt Parquet processing, enhanced caching, and optimized metadata layers, the managed DataLakeCatalog enables federated queries across multiple catalog types within a single query.

➡️ <a href="https://clickhouse.com/blog/query-your-catalog-clickhouse-cloud" target="_blank">Read the blog post</a>

## How Laravel Nightwatch handles billions of observability events in real time with Amazon MSK and ClickHouse Cloud

![image4.png](/uploads/image4_60915058f7.png)

Laravel Nightwatch's observability platform launched with impressive results—5,300 users in the first 24 hours, processing 500 million events on day one, with an average dashboard latency of 97ms. The Laravel team achieved this scale using Amazon MSK and ClickHouse Cloud in a dual-database architecture that separates transactional workloads (Amazon RDS for PostgreSQL) from analytical workloads (ClickHouse Cloud).

The technical foundation includes Amazon MSK Express brokers, capable of handling over 1 million events per second during load testing, with ClickPipes integration eliminating the need for custom ETL pipelines. ClickHouse's columnar architecture delivers 100x faster query performance and 90% storage savings compared to traditional row-based databases, enabling sub-second queries across billions of observability events.

➡️ <a href="https://aws.amazon.com/blogs/big-data/how-laravel-nightwatch-handles-billions-of-observability-events-in-real-time-with-amazon-msk-and-clickhouse-cloud/" target="_blank">Read the blog post</a>

## OLAP On Tap: Untangle your bird's nest(edness) (or, modeling messy data for OLAP)

![image2.png](/uploads/image2_f6f62102bb.png)

Johanan Ottensooser addresses the fundamental tension between efficient data collection (nested, variable JSON) and OLAP performance requirements (predictable, typed columns). Johanan demonstrates how rational upstream patterns, such as flexible transaction schemas with variable metadata, can become performance killers in columnar engines that rely on SIMD operations and low-cardinality filtering.

Three ClickHouse solutions emerge:

* Flattened line-item tables with materialized order views for stable analytics
* Nested() columns for consistent but variable-count arrays
* JSON columns with materialized hot paths for evolving schemas.

The key principle is modeling tables based on query grain and access patterns, rather than the source data structure, thereby moving parsing complexity from query time to ingest time for optimal analytical performance.

➡️ <a href="https://www.linkedin.com/pulse/olap-tap-untangle-your-birds-nestedness-modeling-data-ottensooser-axnhc/" target="_blank">Read the blog post</a>

## Build ClickHouse-powered APIs with React and MooseStack

![image9.png](/uploads/image9_4026c615ca.png)

The 514 Labs team has developed a practical framework for building ClickHouse-powered analytics APIs that integrate seamlessly with existing React/TypeScript workflows. Using MooseStack OLAP, developers can introspect ClickHouse schemas to generate TypeScript types and OlapTable objects, then build fully type-safe analytical endpoints with runtime validation.

The architecture uses ClickPipes for real-time Postgres-to-ClickHouse synchronization, automatic OpenAPI specification generation for frontend SDK creation, and Boreal for production deployment with preview environments and schema migration validation.

➡️ <a href="https://clickhouse.com/blog/clickhouse-powered-apis-in-react-app-moosestack" target="_blank">Read the blog post</a>

## Quick reads

* <a href="https://medium.com/logalarm-devs/from-elasticsearch-to-clickhouse-why-we-migrated-logalarm-siem-c0a8373e1809" target="_blank">Logalarm SIEM migrated from Elasticsearch to ClickHouse</a> to overcome scaling limitations with billions of log events, achieving 70-85% storage reduction and sub-second query performance while solving data consistency issues.
* <a href="https://aws.amazon.com/blogs/big-data/seamlessly-integrate-data-on-google-bigquery-and-clickhouse-cloud-with-aws-glue/" target="_blank">This AWS blog post</a> demonstrates how to use AWS Glue ETL to migrate data from Google BigQuery to ClickHouse Cloud on AWS, leveraging the built-in ClickHouse marketplace connector to eliminate the need for custom integration scripts.
* <a href="http://Stromfee.AI" target="_blank">Stromfee.AI launched a platform</a> that combines ClickHouse database with MQTT IoT data analysis and Langchain MCP (Multimodal Conversation Protocol) to create interactive AI avatars as conversational interfaces for data analysis.
* Furkan Kahvec's research demonstrates <a href="https://medium.com/insiderengineering/clickhouse-query-optimization-argmax-vs-final-50c710a1a7f3" target="_blank">a dynamic approach for choosing between ClickHouse's argMax function and the FINAL modifier</a> based on filter selectivity, achieving up to 40% performance improvements and a 9x reduction in memory usage.
* <a href="https://medium.com/@parade4940/building-a-modern-analytics-extension-for-your-software-e6dbac8254be" target="_blank">Parade's guide</a> demonstrates how to build a modern analytics extension using open-source tools: ClickHouse for fast analytics, Apache Superset for visualization, and dlt for data pipelines, transforming transactional applications into analytically powerful platforms.
* <a href="https://medium.com/@dmitry.bogdanov/industrial-data-and-ai-crash-course-part-2-nano-data-platform-ade2bec8a738" target="_blank">Dmitry Bogdanov's hands-on tutorial</a> builds a containerized "Nano Data Platform" using Kafka for streaming, ClickHouse for time-series storage, and Metabase for visualization to handle industrial IoT data from simulated wind turbines.

## Video corner

* Aaron Katz, ClickHouse’s CEO, was <a href="https://clickhouse.com/videos/aaron-katz-thecube-siliconangle" target="_blank">interviewed as part of theCUBE + NYSE Wired’s Mixture of Experts series</a>.
* Yury Izrailevsky, President of Product & Technology at ClickHouse, <a href="https://creators.spotify.com/pod/profile/ossstartuppodcast/episodes/E182-The-Rise-of-ClickHouse-e3992rl?$web_only=true" target="_blank">joined the Open Source Startup Podcast</a>. In the interview, Yury explained how ClickHouse’s columnar architecture and performance optimizations enable petabyte-scale processing with millisecond query times.
* Mark Needham made videos about three prominent ClickHouse observability use cases: <a href="https://clickhouse.com/videos/petabyte-scale-observability-openai" target="_blank">OpenAI</a>, <a href="https://clickhouse.com/videos/tesla-observability" target="_blank">Tesla</a>, and <a href="https://clickhouse.com/videos/anthropic-observability-at-scale" target="_blank">Anthropic</a>.
* Mark also made a video showing how to <a href="https://clickhouse.com/videos/apache-iceberg-inserts" target="_blank">write to Apache Iceberg from ClickHouse</a>.


Welcome to the October 2025 ClickHouse newsletter, which will round up what’s happened in real-time data warehouses over the last month.

Mark Needham

Blog posts by Mark Needham

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