数据库系统处理死锁一般采用哪两类方法?简述每类方法的基本原理

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解决死锁一般采用死锁预防和死锁检测与恢复两类方法。死锁预防利用死锁预防协议, 通过破坏死锁产生的必要条件来避免系统进入死锁状态,防止死锁发生。死锁检测与恢复则是允许系统进入死锁状态,并且定期检查系统是否发生死锁,当发现系统发生死锁后,采取相应的恢复机制使系统摆脱死锁状态。

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