MergeTree Archives | ChistaDATA Inc.

Elasticsearch to ClickHouse for Logs and Observability: When and How to Switch

Elasticsearch to ClickHouse is the migration we scope most often in observability engagements, and the reason is rarely a feature gap — it is an economics gap. Elasticsearch became the default log store the way […]

The Snowflake Exit: A Migration Framework from Warehouse Credits to ClickHouse

ChistaDATA Inc.

Every quarter we take calls that start the same way: a data platform lead opens their Snowflake invoice, looks at the credit consumption graph, and asks what a Snowflake to ClickHouse migration would save. Sometimes […]

ClickHouse slow query troubleshooting: diagnosing query latency with system.query_log, a ChistaDATA production methodology

Diagnosing Slow ClickHouse Queries with system.query_log: A Production Methodology

ChistaDATA Inc.

Master ClickHouse slow query troubleshooting with a production-proven system.query_log methodology to find, classify, and fix query latency fast.

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ClickHouse Merge Performance: Diagnosing Too Many Parts, Slow Merges, and Stuck Mutations

ChistaDATA Inc.

ClickHouse merge performance is the hinge on which every high-ingest MergeTree deployment turns. When background merges keep pace with inserts, part counts stay flat and SELECT latency stays predictable. When they fall behind, the failure […]

ClickHouse MergeTree Optimization: Sort Keys, Partitioning, Skip Indexes, and Projections

ChistaDATA Inc.

ClickHouse MergeTree optimization is the difference between a table that answers analytical queries in milliseconds and one that scans hundreds of gigabytes for every request. This guide is written for senior engineers who already understand […]

ClickHouse IOPS Troubleshooting: A Complete Guide to Diagnosing and Fixing Disk I/O Bottlenecks

ChistaDATA Inc.

NEEDS FEATURED IMAGE. ClickHouse IOPS troubleshooting guide for DBAs and SREs: diagnose disk I/O bottlenecks with ClickHouse system tables, verify at the OS layer with iostat and pidstat, fix merge storms and part explosion, tune caches, tier storage, and monitor IOPS continuously with Prometheus and Grafana.

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ClickHouse Real-Time POS Analytics: Sub-Second Decisioning for QSR Enterprises

ChistaDATA Inc.

If you’ve spent any time working in QSR (Quick Service Restaurant) data infrastructure, you already know the problem. The need for ClickHouse real-time POS analytics has never been more urgent — millions of POS transactions […]

Data Reliability Engineering for ClickHouse: Principles and Practices

ChistaDATA Inc.

Data Reliability Engineering ClickHouse (DRE) is the discipline that keeps analytical data trustworthy at every stage of its lifecycle — ingestion, transformation, storage, and serving. For teams running ClickHouse as their analytical backbone, DRE is […]

ClickHouse Query Optimization: 8 Indexing Strategies That Actually Work

ChistaDATA Inc.

The ClickHouse indexing strategies that actually move query latency — sorting key, sparse primary index, data-skipping indexes, projections and materialized views — with runnable SQL. Need it faster now? ChistaDATA delivers expert ClickHouse performance tuning, consulting and 24×7 support.

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ClickHouse Primary Index Design: Parts, Partitions and Granules

ChistaDATA Inc.

A practitioner’s deep dive into MergeTree internals — parts, partitions, granules, and primary index design — from the ChistaDATA engineering team.

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