• Autumn’s Newsletter

    Autumn’s Newsletter

    It’s been a while, but we promise we’ve been busy. Since our last update, ClickHouse grew up a lot, there were many new features and enhancements, some of them we reviewed in our blog, others are still waiting for somebody to tell a story about. In this newsletter you can find the latest updates.

  • ClickHouse Meetup in Paris Recap

    ClickHouse Meetup in Paris Recap

    October for us started strong with a successful ClickHouse meetup in Paris. The purpose of the event was to talk about ClickHouse, an open-source column-store analytics DBMS – its features, roadmap, use cases, meet local ClickHouse users, hear talks from ClickHouse lead developer Alexey Milovidov, Altinity CTO Alexander Zaitsev and Paris ClickHouse users.

  • Updates and Deletes in ClickHouse

    Updates and Deletes in ClickHouse

    Oct 16, 2018

    It’s been two years already ago when ClickHouse development team published an excellent blog post “How to update data in ClickHouse”. In that old times ClickHouse supported only monthly partitions, and for mutable data structures, they suggested to use pretty exotic data structures. We were all waiting for a more convenient approach, and finally, it is there: ClickHouse now supports updates in deletes! In this article, we will see how it works.

  • ClickHouse HTTP protocol advanced features

    ClickHouse HTTP protocol advanced features

    ClickHouse HTTP protocol is good and reliable, it is a base for official JDBC, ODBC and many 3rd party drivers and integrations. It can also be used directly with http client libraries. In this article we describe two advanced features of HTTP protocol: execution progress and sessions.

  • Using ODBC with Clickhouse

    Using ODBC with Clickhouse

    20 Sept 2018
    This article shows different ways of how you can use ClickHouse in connection with other data sources to make queries use all of ClickHouse optimization features in order to make results come faster. Also, it is good practice when you have some infrastructure elements already linked to some other data sources or tools that supports ODBC.

  • ClickHouse monitoring with Zabbix

    ClickHouse monitoring with Zabbix

    Altinity is happy to introduce a new tool in ClickHouse environment – Zabbix template for monitoring ClickHouse. It is open source and available on github

    Let’s walk in details on how to install and setup this template.

  • Clickhouse-copier in practice

    Clickhouse-copier in practice

    Clickhouse-copier is a tool designed to copy data from one ClickHouse environment to another. The tool is a part of standard ClickHouse server distribution. It can work in a fully parallel mode and distribute the data in the most efficient way. In this article, we review a few typical examples when clickhouse-copier can be used.

  • Case Study. AfterWords – Intelligent Customer Engagement

    Case Study. AfterWords – Intelligent Customer Engagement

    Aug 1, 2018
    AfterWords is an intelligent customer engagement and survey system that delivers users transactional history and customer feedback to create actionable data to improve operations, sales and profitability.

    In this article, our guest author Oleg Khozyainov shares his experience of using ClickHouse as part of work done for www.surveyafterwords.com

  • Tableau with ClickHouse

    Tableau with ClickHouse

    ClickHouse users often require data to be accessed in a user-friendly way. There is a number of tools that can display big data using visualization effects, charts, filters, etc. Tableau is one of the popular ones. In this article, we will explain how Tableau can be used with ClickHouse data source.

  • ClickHouse and ProxySQL queries rewrite

    ClickHouse and ProxySQL queries rewrite

    ProxySQL is a popular open source, high performance and protocol-aware proxy server for MySQL and its forks. Since September 2017 ProxySQL supports ClickHouse as a backend, so clients can connect to ClickHouse via MySQL protocol. In practice, this helps MySQL-aware applications to start using ClickHouse as without changes in the client library.

    To avoid some limitations to this approach, ProxySQL creator René Cannaò added additional functionality for query rewrite. With his permission, we cross-post his article describing new functionality in our blog.

  • Realtime replication from MySQL to ClickHouse in practice

    July 2, 2018
    Vladislav Klimenko from Altinity and Valery Panov from Ivinco presented a talk at HighLoad Siberia 2018 conference recently. They described the real problem that Ivinco faced and how it has been solved with migration of analytics from MySQL into ClickHouse using MySQL to ClickHouse replication. A few months ago we introduced clickhouse-mysql tool in our blog, and Ivinco was the first company we know that tried it and used it in production.

  • ClickHouse Releases: Upgrade or not Upgrade

    ClickHouse Releases: Upgrade or not Upgrade

    ClickHouse team has released 1.1.54385 version recently. This is yet another bugfixing update in a row of small updates that followed 1.1.54378 release from mid-April. Unfortunately, ClickHouse test coverage is not perfect, and sometimes new features are accompanied by disappointing regressions. ClickHouse team certainly addresses problems in hotfix releases, but ClickHouse streamlined release version numbering makes it not easy to distinguish hotfixes from the feature releases. So how to decide is it safe to upgrade or not?

  • ClickHouse + Graphouse introduction

    ClickHouse + Graphouse introduction

    A few weeks ago we described how to setup ‘ClickHouse monitoring with Graphite’. Today we are going to look at this from a different angle: how ClickHouse can be used as a Graphite backend.

  • Circular Replication Cluster Topology in ClickHouse

    Circular Replication Cluster Topology in ClickHouse

    In some cases, there is a need to configure a distributed cluster with replication but there are not enough servers in order to place every replica on a separate node. It is better to have multiple replicas at the same nodes configured in a special way, that allows to continue executing queries even in the case of a node failure. Such replication configuration can be found in different distributed systems, it is often referred to as ‘circular’ or ‘ring’ replication. In this article, we will discuss how to set up circular replication in ClickHouse.

  • ClickHouse Meetups at Bay Area. Recap

    We would like to thank all attendees, our great partners, talented speakers, and generous hosts, who made these events possible and successful!

    Presentations from meetups are published here.

  • ClickHouse release 1.1.54380

    ClickHouse team and community contributors actively develop ClickHouse adding many new features, improving performance and flexibility. Unfortunately, sometimes it affects stability of the product. We were very upset by some unexpected regressions in recent ClickHouse releases. After initial testing of latest 1.1.54380 version we think it may be a good candidate for the new stable release. Previous releases free from severe issues were aged 1.1.54292 and 1.1.54327.

    ClickHouse 1.1.54380 is available in Yandex and Altinity repositories. So what’s new and important in 1.1.54380 and previous release 1.1.54378.

  • ClickHouse Monitoring with Graphite

    ClickHouse Monitoring with Graphite

    Monitoring is an important part of operating any software in production. The proper monitoring solution needs to store metrics somewhere as well as provide visualization capabilities. ClickHouse does not have such a tool packaged, but there are several 3rd-party monitoring solutions that can be used. In this article, we will describe how to configure Graphite for monitoring ClickHouse metrics.

  • Analyze MySQL Audit Logs with ClickHouse and ClickTail

    Analyze MySQL Audit Logs with ClickHouse and ClickTail

    In this blog post, I’ll look at how you can analyze MySQL audit logs (Percona Server for MySQL) with ClickHouse and ClickTail.  Audit logs are available with a free plugin for Percona Server for MySQL. Besides providing insights about activity on your server, you might need the logs for compliance purposes.