Optimize table (force merge) clickhouse
Force merging of all parts (use with caution on large tables)
clickhouse-client -q 'OPTIMIZE TABLE mydb.mytable FINAL'
more clickhouse
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Ingest CSV from file
clickhouse-client --query 'INSERT INTO mydb.events FORMAT CSVWithNames' < events.csv
Check replication status
clickhouse-client -q 'SELECT database, table, is_leader, queue_size, absolute_delay FROM system.replicas WHERE absolute_delay > 0'
Slowest recent queries
clickhouse-client -q "SELECT query_duration_ms, formatReadableSize(memory_usage) mem, substring(query,1,80) FROM system.query_log WHERE type=2 AND event_time>now()-3600 ORDER BY query_duration_ms DESC LIMIT 10"
Pending mutations
clickhouse-client -q "SELECT database, table, mutation_id, latest_fail_reason FROM system.mutations WHERE is_done=0"
Connect to clickhouse-client
clickhouse-client -h clickhouse -u default --password <pass> --database mydb