DWS manages cluster transactions, the basis of HA and failovers. This ensures speedy fault recovery, guarantees the ACID properties for transactions and after a recovery, and enables concurrent control.
DWS provides an HA mechanism to reduce the service interruption time when a cluster is faulty. It protects key user programs to continuously provide external services, minimizing the impact of hardware, software, and human faults on services and ensuring service continuity.
- Hardware HA: Disk RAID, switch stacking, NIC bond, and uninterruptible power supply (UPS)
- Software HA: HA mechanism used for instances in the DWS cluster, such as CNs, GTMs, and DNs)
- Transaction blocks are supported. You can run start transaction to explicitly start a transaction block.
- Single-statement transactions are supported. If you do not explicitly start a transaction, a single statement is processed as a transaction.
- Distributed transaction management and global transaction information management are supported. This includes gxid, snapshot, timestamp management, distributed transaction status management, and gxid overflow processing.
- Distributed transactions have ACID properties.
- Deadlock prevention in a distributed system is supported. Transaction deadlocks are prevented, or transactions are automatically unlocked once deadlocked.