altinity-expert-clickhouse-merges

Diagnostics

Run all queries from checks.sql in this skill's directory (cluster-wide) one by one and produce a decision-ready report.

Triage Order (Mandatory)

1. Check current active merges from system.merges.
2. Check merge success/failure trend from system.part_log.
3. Check table-level status (merge_ok, merge_failed, last success/failure).
4. Check merge reason + algorithm (merge_reason, merge_algorithm).
5. Check merge RAM now + historical peak RAM (system.merges.memory_usage, system.part_log.peak_memory_usage).
6. Check part-count offenders with split:
   • database = 'system'
   • database != 'system'
7. Check relevant settings, including TTL merge concurrency.

Decision Rules