MongoDB (0)-Preface

I. Advantages and Disadvantages of MongoDB:

1. Advantages:

A. Superior performance:

Thanks to the advantages of the design and the compilation in C ++, the performance is superior. Test Data parameters :.

B. JSON operation and storage:

Mongo supports a wide range of JSON-style Query expressions to easily query data in various formats in documents. It is perfect for document-style storage requirements. At the same time, JSON is widely used in today's popular webapis, low entry level,ProgramThe staff became happier :)

C. mapreduce engine, step-by-step cloud computing is possible.

2. Deficiency:

A. SQL is not supported. It does not have the reuse advantage of traditional relational database experience-level model solutions, nor can it use database-based closed logic solutions, such as views and triggers.

B. Currently, transactions are not supported and are not suitable for transaction scenarios.

C. Emerging nosql databases are not stable enough. There are many bugs and some failure cases have been found. The automatic balancer does not work as perfectly as expected, and the document granularity is small. If the data migration is not reasonable enough, the storage fragmentation problem will occur (to be verified ).

D.

 

Ii. Applicable and applicable scenarios:

1. inapplicable scenarios:

A. strict transactional systems: Why do we say strict transactional systems, because some non-strict transaction systems occasionally use some transactions, the purpose is to ensure data consistency and timeliness to a certain extent. In this case, some methods can be used to simulate or replace the data, such as global locks. However, strict transactional systems, such as banks and e-commerce, require strict atomic transaction operations. MongoDB has not been able to meet such requirements so far.

B. Commercial analysis systems. These are more suitable for processing with traditional SQL-related data warehouses.

2. Applicable scenarios:

A. High concurrency requires a distributed massive data system:

B. website data: Mongo is ideal for real-time insertion, update, and query. It also supports the replication and high scalability required for real-time website data storage.

C. Any extended data center:

 

To be continued ------------------------