Blog:Unlock Powerful ClickHouse Insights – ChistaDATA’s Expert Analytics Blog

ClickHouse TTL: How Deletes Are Scheduled and 6 Reasons They Fail

A ClickHouse TTL clause is not a delete queue. There is no background reaper walking rows and checking expiry timestamps. A TTL expression on a MergeTree table is a promise that expired rows will be […]

ClickHouse Partition Pruning vs Primary Key: 3 Proven Gates

ChistaDATA Inc.

ClickHouse partition pruning and primary-key pruning are two different mechanisms that happen to show up on the same summary line of the server log, which is why so many people treat them as one thing. […]

Lakehouse ClickHouse With 3 Signed SLOs: Proven DAPE Platform

ChistaDATA Inc.

Lakehouse ClickHouse sold as an engineered platform: ChistaDATA DAPE signs SLOs for freshness across tiers, p95/p99 per tier and query class, and a measured cost curve — commitments that neither software-plus-support nor cloud-consumption contracts carry. With SQL, storage-policy config, and diagrams.

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ClickHouse Sharding Troubleshooting and Performance Optimization

ChistaDATA Inc.

A field guide to ClickHouse sharding troubleshooting: Distributed send-queue backlogs, duplicate rows from internal_replication, shard skew, initiator merge bottlenecks, distributed JOIN failures and unavailable shards, each with the system.* evidence, the mechanism, the staged fix, and the alert that catches it early.

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

ChistaDATA Inc.

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 26.x in production: QBit vectors, text index GA, and Iceberg writes

ClickHouse 26.x in Production: QBit Vectors, Text Index, and Iceberg Writes

ChistaDATA Inc.

ClickHouse 26.x ships monthly on calendar versioning (YY.MM), and the ClickHouse 26.x line has been the most consequential run of releases since the project went commercial. As of August 2026, the latest stable is v26.7.3.19 […]

ClickHouse Performance

ClickHouse Performance Troubleshooting: 9 Proven Techniques for 26.7

ChistaDATA Inc.

ClickHouse performance troubleshooting is mostly a reading problem, not a tooling problem. A 26.7 server already writes down almost everything you need — every query it ran, every byte it touched, every microsecond each operator […]

ClickHouse Upgrade Guide: 6 Proven Steps for Zero-Downtime Rolling LTS Upgrades

ChistaDATA Inc.

A production ClickHouse upgrade done properly is a rolling, replica-by-replica operation with zero query downtime, a measured before/after regression check, and a rollback posture decided before the first package is installed. Done casually, it is […]

ClickHouse BYOC with ChistaDATA: The Complete 2026 Architecture Guide

ChistaDATA Inc.

ClickHouse BYOC (Bring Your Own Cloud) is a deployment model in which the entire ClickHouse® data plane runs inside your cloud account and your VPC, while ChistaDATA operates, tunes, secures and supports that cluster through […]