Back to our example, if you were using the MyISAM engine, you could be in trouble, because MyISAM does not enforce atomicity. Hence, a single change can be partially applied, whereby some rows in the intended set are affected, but the rest of the set are not. On the other hand, the...
In the above example, user B may withdraw $100 only after user A’s transaction is completed and is updated in the database. If the system fails before A’s transaction is logged in the database, A cannot withdraw any money, and Z’s account returns to its previous consistent state....
ACID,是指数据库管理系统(DBMS)在写入/更新资料的过程中,为保证事务(transaction)是正确可靠的,所必须具备的四个特性:原子性(atomicity,或称不可分割性)、一致性(consistency)、隔离性(isolation,又称独立性)、持久性(durability)。 在数据库系统中,一个事务是指:由一系列数据库操作组成的一个完整的逻辑过程。例如...
ACID,是指数据库管理系统(DBMS)在写入/更新资料的过程中,为保证事务(transaction)是正确可靠的,所必须具备的四个特性:原子性(atomicity,或称不可分割性)、一致性(consistency)、隔离性(isolation,又称独立性)、持久性(durability)。 在数据库系统中,一个事务是指:由一系列数据库操作组成的一个完整的逻辑过程。例如...