TiDB is a distributed SQL database with MySQL-oriented syntax and protocol. That does not make every MySQL application behavior identical.
Clone a representative schema and run the real application test suite against TiDB and a candidate. Focus on transaction isolation, constraints, auto-increment assumptions, stored procedures or unsupported SQL, and reporting queries. Load enough data to exercise distribution, then simulate a node loss and inspect latency and retry behavior. Rehearse backup and restore separately from high availability.
TiDB's architecture FAQ explains the compatibility target, while its backup overview covers recovery. A migration is proven by application correctness and restore time, not a successful connection string.
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