How to setup 6 nodes ClickHouse replication and sharding?

Configuring six nodes ClickHouse replication and sharding ClickHouse implements replication and sharding through a combination of distributed tables and replication settings. Replication in ClickHouse is implemented by creating a cluster of servers, each of which contains a copy of the same data. When a change is made to the data on one server, it is […]

Swiss PGDay 2022

The Swiss conference on PostgreSQL Swiss PGDay 2022 Friday, July 1, 2022 OST Eastern Switzerland University of Applied Sciences, Campus Rapperswil (Switzerland) Covid-19: No pandemic-related restrictions are expected on the Rapperswil campus. Nevertheless, we appeal to the personal responsibility and tolerance of participants for a healthy and safe event. This day is all about PostgreSQL […]

How to Restore/Recover ClickHouse after ZooKeeper Metadata is corrupted/lost?

How to Restore/Recover ClickHouse after ZooKeeper Metadata is corrupted/lost? When you are building a highly available ClickHouse Infrastrstucture for scale and performance we use ZooKeeper for ClickHouse Replication Management and Operations with ReplicatedMergeTree table engine. You can expect ZooKeeper to face data loss (or a very complex corruption scenario) due to either human error or […]

ClickHouse DR Strategies

ClickHouse DR Strategies We at ChistaDATA never recommend Replication Solution as an alternative for Backup or DR. Replication focuses on business continuity, i.e. delivering uninterrupted data infrastructure availability to mission-critical ClickHouse Operations and Backup involves creating a copy or copies of an existing set of data so that in case of a data loss, the […]

What is new ClickHouse 22.2

ClickHouse 22.2 New Features  ClickHouse Development Group is very active (, We at ChistaDATA carefully evaluate new features to recommend customers for adoption (whenever appropriate). Our Support team is committed to providing maximum value for ChistaDATA customers for building optimal, scalable and reliable ClickHouse infrastructure operations. In this blog post we have explained what is […]

ClickHouse LowCardinality Data Type

ClickHouse LowCardinality Data Type ClickHouse LowCardinality feature is not documented in detail and people still mistake the functional relevance of ClickHouse LowCardinality. ClickHouse has several data types and SQL implementation which is entirely different from other data warehousing systems, Few of them even doesn’t exist. In this post we have explained how ClickHouse LowCardinality works […]

Why I am not able to connect to ClickHouse?

Troubleshooting ClickHouse – Why I am not able to connect to ClickHouse?  Why I am not able to connect with ClickHouse Server? We often this ticket on our support function and the error will be like “Connection reset by peer while reading from socket”. So we have a standard, yet simple approach to troubleshooting ClickHouse […]

How ClickHouse Query Profiler works ?

How does ClickHouse Query Profiler work? The core objective of ClickHouse Query Profiler is to measure the performance metrics of SQLs and understand where the application is spending most of the time, This helps to successfully complete ClickHouse performance audit/diagnostics/forensics by tracing CPU time against wall-clock time including idle time. At ChistaDATA we spend a […]

Connecting to ClickHouse with C++ client libraries

ClickHouse C++ client – Connecting to ClickHouse with C++ client libraries ClickHouse C++ client is a client library for C++ development allowing applications to connect to ClickHouse databases based on the clickhouse-native-client library. The library was originally developed by the ClickHouse core community development teams and we at ChistaDATA maintain the fork for the same […]

Installing BCC on Ubuntu for Troubleshooting Full-Stack Performance

Installing BCC for Troubleshooting Full-Stack Performance Software Infrastructure Observability allows Data Ops. Engineers, SREs and other stakeholders in the ecosystem to easily identify components that need to be tuned proactively for optimal performance. Faster transactions accelerate our customer technology infrastructure. BPF Compiler Collection (BCC) is a collection of tools for Linux Kernel tracing which makes use […]