InnoDB is the default storage engine (From MySQL 5.6)
- a transaction-safe (ACID compliant)
- that has commit, rollback, and crash-recovery capabilities
- FOREIGN KEY referential-integrity constraints.
- row-level locking (without escalation to coarser granularity locks)
- and Oracle-style consistent nonlocking reads increase multi-user concurrency and performance.
InnoDB stores user data in clustered indexes to reduce I/O for common queries based on primary keys.