acid

What is the relationship between ACID and database transaction? Does ACID give database transaction or is it the same thing? Could someone enlighten this topic. ACID is a set of properties that you would like to apply when modifying a database. Atomicity Consistency Isolation Durability A transaction is a set of related changes which is used to achieve some of the ACID properties. Transactions are tools to achieve the ACID properties. Atomicity means that you can guarantee that all of a transaction happens, or none of it does; you can do complex operations as one single unit, all or nothing,

Is there any NoSQL data store that is ACID compliant? AJ. I'll post this as an answer purely to support the conversation - Tim Mahy , nawroth , and CraigTP have suggested viable databases. CouchDB would be my preferred due to the use of Erlang , but there are others out there. I'd say ACID does not contradict or negate the concept of NoSQL ... While there seems to be a trend following the opinion expressed by dove , I would argue the concepts are distinct. NoSQL is fundamentally about simple key-value (e.g. Redis) or document-style schema (collected key-value pairs in a "document" model, e.g.

在分布式存储领域，为了增加系统的高可用性，经常将同一份数据存储多个副本，常见的做法的三备份。但是此做法也引来了数据一致性的问题。为了解决数据一致性的问题，业界常用的有CAP、ACID、BASE等理论模型。 CAP原则 CAP是对强一致性（Consistency）、可用性（Availability）、分区容忍性（Partition Tolerance） 的一种简称。 强一致性：即在分布式系统中同一数据多副本的情况下，对数据的更新操作体现出的效果与只有单份数据是一样的。 可用性：客户端在任何时刻对分布式系统的读写操作都应保证在限定延时内完成。 分区容忍性：即使分区机器间无法进行网络通信仍能继续工作。 CAP原则最初由Eric Brewer于1999年提出，他同时证明：对于一个大型分布式系统，CAP三者不可兼得。即要么AP，要么CP，要么AC，不存在CAP。 ACID原则 在关系型数据库领域经常采纳ACID原则，即原子性（Atomicity）、一致性（Consistency）、事务独立性（Isolation）、持久性（Durability） 原子性：指一个事务要么全部执行，要么完全不执行，不允许一个事务执行一半就停止。 一致性：事务的开始和结束时，硬始终满足一致性约束条件。 事务独立性：如果有多个事务同时执行，彼此之间不需要知晓对方的存在。不允许出现两个事务交错、间隔执行部分任务的情形