Nov 15, 2018
Once upon a time we spotted TSBS (https://github.com/timescale/tsbs) -- Time Series Benchmark Suite, started by InfluxDB engineers and polished to perfection by TimescaleDB team. The suite allows to compare apples-to-apples when testing different databases: it is a framework to generate test data, load it to different databases, run test queries, and collect statistics to analyse. We could not resist adding ClickHouse to the list of supported databases. It turned out that ClickHouse --- being a general purpose analytical DBMS -- stands very well against proven time series databases. Those benchmarks highlighted strengths and weaknesses of different technologies. Interested? Let’s dig into details.
Nov 15, 2018
Nov 5, 2018
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.Read More
Oct 19, 2018
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.
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.Read More
Oct 3, 2018
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.Read More
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.
Aug 22, 2018
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.
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.
July 19, 2018
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.
July 16, 2018
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.Read More
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.
June 4, 2018
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?
May 10, 2018
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.
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.Read More
Apr 25, 2018
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.Read More
LONDON, April 23, 2018 /PRNewswire/ -- Altinity, a leading service provider for ClickHouse, today announced explosive 10x quarter-over-quarter revenue growth in Q1 2018 for its ClickHouse services. The spike in demand for ClickHouse Support mirrors the trend of companies increasingly relying on ClickHouse as a solution for their data analytics and data warehousing needs.Read More
Apr 20, 2018
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.
Apr 6, 2018
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.