Distributed cap principle

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CAP Definition

Consistency Uniformity : All nodes have the same data at the same time . Consistency can be divided into the following three types :
Strong consistency : After update operation , Subsequent operations must get the updated results
Weak consistency : After update operation , Subsequent operations can tolerate some or all of the updates
Final consistency : After update operation , After a period of time, it is required to be able to get the updated results
Availability Usability : The service is consistently available within normal response time
Partition Tolerance Partition tolerance : When a distributed system encounters a node or network partition failure , Still be able to provide external services to meet the consistency or availability

Application scenarios

CA without P Abandon system scalability , No child nodes , For example, a single node relational database
CP without A Maintain strong consistency in distributed servers , But it may lead to long synchronization time , For example, distributed database redis
AP without C Give up consistency , Keep high availability . Each node uses local data to provide services . Make the global data inconsistent . Such as using mobile online shopping , May be available when browsing products , But when you place an order, the system tells you that the order failed .

Please correct me if there is any mistake