ClickHouse Internals Archives | Page 3 of 18

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 v/s PostgreSQL & MySQL for Real-time Analytics

Shiv Iyer

“ClickHouse, with its columnar storage approach, is inherently suited for high-velocity data ingestion and real-time analytics, offering superior performance, scalability, and cost-effectiveness, making it a strategic choice for organizations seeking real-time insights and decision-making.” Introduction […]

ClickHouse JOINs: Understanding the Internal Mechanics of JOIN operations

ClickHouse JOIN: Understanding the Internal Mechanics of JOIN operations

Shiv Iyer

Introduction ClickHouse JOINs operations are executed differently compared to traditional SQL databases, primarily due to its columnar storage architecture and distributed data processing capabilities. Understanding how ClickHouse JOINs work internally involves looking at the types […]

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 Security: ClickHouse Data Masking

ClickHouse Data Masking for Regulatory Compliance

Shiv Iyer

Masking data in ClickHouse for data security and compliance involves altering the representation of the data to protect sensitive information. Data masking is essential in scenarios where you need to share data without exposing sensitive details, such as in development environments or with third-party analysts.

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Comprehensive Guide for ClickHouse Horizontal Scaling and Capacity Planning

Shiv Iyer

Calculating your company’s required real-time analytics capacity on ClickHouse involves several steps and considerations. It’s important to assess current and projected data volumes, query complexity, and the expected concurrency of queries.

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ClickHouse Horizontal Scaling: Optimal Read-Write Split Configuration and Execution

Shiv Iyer

Scaling ClickHouse horizontally while optimizing the split between read and write operations is a multi-step process that involves setting up a cluster with sharded and replicated tables.

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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 Index Granularity: Tuning index_granularity for Performance

Shiv Iyer

Understanding index granularity is crucial for troubleshooting performance issues in ClickHouse, especially when it comes to optimizing how ClickHouse uses indexes for query execution.

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* 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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