ClickHouse Performance Archives

When ClickHouse Queries Get “Stuck”

When ClickHouse Queries Get “Stuck”: Detecting, Analyzing, and Safely Killing Problematic Sessions ClickHouse is a high-performance columnar database management system designed for online analytical processing (OLAP). While it excels at handling large-scale data analytics workloads, […]

SQL Antipatterns in ClickHouse

ChistaDATA Inc.

Analyzing Common SQL Antipatterns in ClickHouse and Best Practices for High Performance ClickHouse is renowned for its ability to process trillions of rows in milliseconds, making it a powerhouse for real-time analytics. However, this performance […]

Monitoring Merge Queues in ClickHouse

Shiv Iyer

Monitoring Merge Queues in ClickHouse: Detecting and Resolving Merge Pressure ClickHouse, renowned for its high-performance columnar storage and analytical query capabilities, relies heavily on its underlying Log-Structured Merge-Tree (LSM-Tree) architecture to achieve exceptional write throughput […]

Using system.query_thread_log for Low-Level ClickHouse Performance Insights

ChistaDATA Inc.

Using system.query_thread_log in ClickHouse for Low-Level Performance Insights Introduction to Thread-Level Query Analysis In the realm of high-performance analytical databases, ClickHouse stands out for its ability to process massive datasets at lightning speed. However, as […]

Setting Up ClickHouse Alerts: Detecting Performance Degradation Before It Impacts Users

ChistaDATA Inc.

Setting Up ClickHouse Alerts: Detecting Performance Degradation Before It Impacts Users ClickHouse is a powerful column-oriented database management system designed for real-time analytical processing, capable of handling massive datasets with exceptional speed. However, like any […]

ClickHouse Complete Guide to LowCardinality

ChistaDATA Inc.

ClickHouse Complete Guide to LowCardinality: When and How to Use It Introduction ClickHouse, the high-performance columnar database management system, offers a specialized data type called LowCardinality that serves as a powerful optimization tool for specific […]

Setting up Alerts in ClickHouse for Performance Troubleshooting

ChistaDATA Inc.

Setting Up Alerts: Detecting ClickHouse Performance Degradation Before It Impacts Users Proactive alerting is a critical operational practice that prevents incidents by identifying performance degradation before it affects end users 4. This comprehensive guide demonstrates […]

ClickHouse Storage Tiering Best Practices: Moving Data Between Hot and Cold Storage with TTL

ChistaDATA Inc.

ClickHouse Storage Tiering Best Practices: Moving Data Between Hot and Cold Storage with TTL Efficient data management is critical for modern analytical databases, especially when dealing with large volumes of time-series or event-driven data. ClickHouse, […]

ClickHouse Search: Case-sensitive Searches with UPPER & LOWER Functions

Boosting Materialized View Performance

ChistaDATA Inc.

Aggregation States: Boosting Materialized View Performance by 10x in ClickHouse ClickHouse has long been celebrated for its lightning-fast analytical query performance, especially when handling massive datasets in real time. One of the most powerful features […]

ClickHouse Performance: Estimated & Actual Row Counts in Execution Plans

PREWHERE vs WHERE in ClickHouse Queries

ChistaDATA Inc.

PREWHERE vs WHERE: When and How to Optimize Your ClickHouse Queries Introduction Query performance in ClickHouse often hinges on how efficiently you filter data. While most SQL users are familiar with the WHERE clause, ClickHouse […]