query-analyzer

To diagnose slow ClickHouse queries, this skill inspects system.query_log metrics like read_rows, memory_usage, and query_duration_ms to pinpoint runtime bottlenecks and heavy table scans. It then provides a targeted optimization plan.

ClickHouse EXPLAIN plan analysis reveals execution paths using indexes and pipeline actions. This skill leverages EXPLAIN outputs to identify inefficient joins, missing partition pruning, and poor index usage to guide query optimization.

You need access to a running ClickHouse instance with permissions to execute SHOW CREATE TABLE, DESCRIBE TABLE, EXPLAIN, and system.query_log auditing to perform schema assessment and runtime performance analysis.

Yes, you can optimize slow report workloads by identifying heavy scans, bad joins, and missing partition pruning. The skill assesses table structure and runtime metrics to recommend targeted schema and query changes.

The best way to check for missing partition pruning is by running SHOW CREATE TABLE and DESCRIBE TABLE to understand partitioning implications. This skill combines schema assessment with EXPLAIN plan analysis to detect inefficient scans.

Your ClickHouse query likely lacks proper partition pruning or uses inefficient filters. This skill audits system.query_log to compare read_rows against result_rows and read_bytes, identifying heavy full-table scans causing the inefficiency.