ChistaDATA Archives | Page 10 of 34

Implementing Online Schema Change in ClickHouse

Introduction In the dynamic world of data management, databases are constantly evolving to meet the changing needs of organisations. However, changing the structure of a database, also known as a schema change, has traditionally been […]

ClickHouse December 2023 Release – v23.12

ChistaDATA Inc.

Introduction : ClickHouse Release Notes Every new release includes new features, enhancements, and numerous bug fixes, and the ChistaDATA team always stays on top of the latest releases. On December 29, 2023, ClickHouse version 23.12 […]

ClickHouse November 2023 Release – Version 23.11

ClickHouse November 2023 Release – v23.11

ChistaDATA Inc.

Introduction: ClickHouse Release Note Every new release includes new features, enhancements, and numerous bug fixes, and the ChistaDATA team always stays on top of the latest releases. On December 06, 2023, ClickHouse version 23.11 was […]

ClickHouse Performance: Optimizing HASH GROUP BY and ORDER BY Queries

ClickHouse HASH GROUP BY: Optimizing GROUP BY and ORDER BY Queries

Shiv Iyer

Introduction : ClickHouse HASH GROUP BY In the realm of database management, particularly with ClickHouse, query optimization is a critical aspect of ensuring efficient data processing and retrieval. Among the various queries, HASH GROUP BY […]

ClickHouse Troubleshooting: Understanding Estimated I/O and CPU Costs

Shiv Iyer

Introduction In ClickHouse, like many database systems, performance troubleshooting and query optimization often involve understanding various metrics, including estimated I/O (Input/Output) costs and estimated CPU (Central Processing Unit) costs. These metrics are crucial for identifying […]

ClickHouse Case-Sensitive Search with UPPER & LOWER Functions

Shiv Iyer

Implementing a case-sensitive search in ClickHouse, a column-oriented database management system, can be achieved by using the UPPER or LOWER functions. These functions convert text data to either uppercase or lowercase, respectively, allowing for a consistent comparison.

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Overview of ClickHouse Architecture and Query Performance Techniques

Shiv Iyer

Introduction: ClickHouse Architecture Understanding the internals of ClickHouse reveals why it’s renowned for its exceptional performance, especially in the realm of online analytical processing (OLAP). ClickHouse is a column-oriented database management system (DBMS) that employs […]

ClickHouse High-Volume Data Ingestion: Server Configuration Guide

Shiv Iyer

Optimizing ClickHouse for high-velocity and high-volume data loading involves several server configuration and tuning techniques.

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Troubleshooting Underutilised ClickHouse Indexes

ClickHouse Troubleshooting: Why is ClickHouse Index Underutilised?

Shiv Iyer

If a ClickHouse index is not being utilized for existing data, leading to full table scans even after creating the index, several factors could be at play.

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ClickHouse MergeTree: Overview of ClickHouse Storage Engines

Shiv Iyer

Introduction ClickHouse supports several storage engines, each optimized for different use cases. Understanding the characteristics of each engine can help you choose the right one for your specific needs, thereby improving performance. ClickHouse MergeTree Engine […]

* Everything changes over time – Our blogs/posts and comments changes over time, That’s how it should be! Whatever we comment from ChistaDATA Inc. Teams (including Shiv Iyer) and other stakeholders or guest bloggers posted here are never permanent, These things worked for us. But, there is no guarantee they will work for you too, When using the recommendations from ChistaDATA or MinervaDB or MinervaSQL or any other online resources / Google, You must test the advice before applying them to your production systems, and always invest for a robust Database DR solution, Thank you for understanding.

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