Two Approaches to Synchronize MySQL with Redis Cache: UDF Trigger and Binlog Parsing (Canal)

Solution 1 (UDF)

Describes using MySQL triggers together with a user‑defined function (UDF) that writes changed rows directly into Redis, providing immediate cache updates; this approach suits read‑heavy, write‑light scenarios but can degrade performance because triggers add overhead on every write.

Solution 2 (Binlog Parsing)

Explains how to parse MySQL binary logs to capture data modifications and push them to Redis, effectively treating Redis as a slave that receives the master’s binlog events, allowing asynchronous synchronization without altering the MySQL schema.

Canal Open‑Source Tool

Introduces Alibaba’s Canal project, a pure Java solution that simulates a MySQL slave, receives binlog streams via the dump protocol, parses the binary log bytes, and exposes the data for further processing such as writing to Redis.

Additional Considerations

Mentions alternative patterns like writing to Redis first and later syncing to MySQL, warning that this can be unsafe because a temporary Redis outage may cause data loss; the article also includes diagrams and notes on the complexity of binlog format handling.