ProxySQL vs TiCDC

ProxySQL is a self-hosted Linux database proxy for MySQL, PostgreSQL and related systems. It scales infrastructure without changes to the application stack or database engine, multiplexing more than 100,000 client connections through a few hundred backend connections. Protocol-aware, regex-based routing can send queries to primary servers, replicas or shards, and can route by user, schema or table. The proxy can cache results without application changes, monitor backend health and reroute traffic during failures. Query mirroring duplicates live traffic for analysis and performance testing, while percentage-based balancing supports gradual shifts. A database firewall is intended to protect against SQL injection and runaway queries. Deployment options include Linux packages, Docker and Kubernetes. ProxySQL is GPLv3-licensed open source, released in 2013. The Community plan is free and includes core features, supported platforms and community channels.

TiCDC is a free, open-source, self-hosted tool for replicating incremental data changes from TiDB. It captures TiKV change logs, sorts the changes, and exports row-based data to systems including TiDB, MySQL-compatible databases, Kafka, Amazon S3, GCS, Azure Blob Storage, and NFS. Recommended Kafka formats include Canal-JSON, Avro, and Debezium. Filters can select databases, tables, DMLs, and DDLs, while the Open API can check task status, change task configuration, and create or delete tasks. TiCDC supports replication between TiDB clusters for disaster recovery, with second-level RPO and minute-level RTO, as well as bidirectional replication for multi-active deployments. It can be deployed with a new cluster or added to an existing one; production guidance recommends at least two instances. The system has no single point of failure and allows nodes to be added or removed dynamically. Delivery is at least once, so failures can lead to repeated statements or Kafka messages.