clickhouse-debug-bundle

# ClickHouse Debug Bundle ## Overview Collect comprehensive diagnostic data from ClickHouse system tables for troubleshooting performance issues, merge problems, or support escalation. ## Prerequisites - Access to ClickHouse with `system.*` table read permissions - `curl` or `clickhouse-client` available ## Instructions ### Step 1: Server Health Overview ```sql -- Server version and uptime SELECT version() AS version, uptime() AS uptime_seconds, formatReadableTimeDelta(uptime()) AS uptime_human, currentDatabase() AS current_db; -- Global metrics snapshot SELECT metric, value, description FROM system.metrics WHERE metric IN ( 'Query', 'Merge', 'PartMutation', 'ReplicatedFetch', 'TCPConnection', 'HTTPConnection', 'MemoryTracking', 'BackgroundMergesAndMutationsPoolTask' ); ``` ### Step 2: Disk and Table Health ```sql -- Disk usage by table (top 20) SELECT database, table, formatReadableSize(sum(bytes_on_disk)) AS disk_size, sum(rows) AS total_rows, count() AS active_parts, max(modification_time) AS last_modified FROM system.parts WHERE active GROUP BY database, table ORDER BY sum(bytes_on_disk) DESC LIMIT 20; -- Tables with too many parts (merge pressure) SELECT database, table, count() AS parts FROM system.parts WHERE active GROUP BY database, table HAVING parts > 100 ORDER BY pa...