CHEATSHEET

TODOs

• löschen von orgs?
• default table
• Lösung: Wie clickhouse überhaupt ansprechen als Benutzer? (appgw erlaubt nur http)
  => Wie kann nutzer daten selbst nach clickhouse bekommen?
• [ ]

Query Monitoring

SELECT * FROM system.processes;

Last 5 Finished Queries

SELECT
    event_time,
    user,
    query_duration_ms,
    read_rows,
    result_rows,
    memory_usage,
    query
FROM system.query_log
WHERE type = 'QueryFinish'
ORDER BY event_time DESC
LIMIT 5;

Top 5 Slowest Queries

SELECT
    event_time,
    query_duration_ms,
    read_rows,
    memory_usage,
    query
FROM system.query_log
WHERE type = 'QueryFinish'
ORDER BY query_duration_ms DESC
LIMIT 5;

Last 5 Failed Queries

SELECT
    event_time,
    query_duration_ms,
    exception,
    query
FROM system.query_log
WHERE type = 'ExceptionWhileProcessing'
ORDER BY event_time DESC
LIMIT 5;

Top 5 Most Frequent Queries

SELECT
    query,
    count() AS cnt
FROM system.query_log
WHERE type = 'QueryFinish'
GROUP BY query
ORDER BY cnt DESC
LIMIT 5;