Module 8: Observability, Monitoring & System Tables
- Introduction to key ClickHouse system tables (system.metrics, system.events, system.query_log)
- Monitoring query performance and resource usage using system.query_log
- Identifying essential server metrics (CPU, Memory, Disk I/O, Network)
- Integrating ClickHouse metrics with tools like Prometheus & Grafana (conceptual overview)
- Basic troubleshooting using logs and system tables
Module 7: Querying Data: SELECT, Aggregations, and Functions
- Writing SELECT queries with WHERE, ORDER BY, LIMIT
- Performing powerful aggregations using GROUP BY and aggregate functions (count, sum, avg, uniq, etc.)
- Utilizing common ClickHouse functions (String, Date/Time, Array, Conditional)
- Understanding JOIN syntax and performance considerations in ClickHouse
- Working with subqueries and WITH clauses
Module 6: Replication & High Availability
- Understanding the need for data replication and fault tolerance
- Using the ReplicatedMergeTree family of engines
- Configuring replicas and clickhouse-keeper paths for tables
- Monitoring replication status and lag
- Handling replica recovery and consistency considerations
Module 5: ClickHouse Clustering: Sharding & Distributed Tables
- Clustering Architecture: Shards and Replicas concepts
- Role of {Zoo,Clickhouse}Keeper in managing cluster state and replication.
- Configuring cluster topology in config.xml
- Using the Distributed table engine to query across shards
- Understanding the Distributed DDL Queries