MongoDB (i)--Brief introduction

These two days a simple study of the MongoDB database, belong to the NoSQL type database, a simple macroscopic look at NoSQL knowledge and MongoDB basic knowledge.

NoSQL is not just SQL abbreviation, it refers to the relational database, which is different from the oracle,mysql,sqlserver and other commonly used relational database. It is in the form of Key-value, the form of JSON data that we are familiar with.

Development: NoSQL is with the rise of the Internet Web2.0 Web site, the traditional relational database in dealing with the web2.0 site, especially the large-scale data and high concurrency of the SNS type of web2.0 pure Dynamic Web site has become powerless, exposing a lot of insurmountable problems, and NoSQL is to cope with these problems appear, and continue to develop. The beginning is the Google Company's bigtable, Taobao data platform Tair, Visual Chinese website MongoDB and so on behalf of NoSQL's continuous development.

The reason for the rapid development of NoSQL: with the continuous development of the Internet, various types of applications are emerging, so in this era of cloud computing, the technology put forward more demand. Although the relational database has an unshakable position in the industry's data storage, due to its inherent limitations, it is difficult to meet several of the above requirements: expansion difficulties, slow reading and writing, high cost, limited support capacity. But NoSQL focus on data high concurrent read and write and storage of massive data, compared with relational database, they have weakened in architecture and data model, and have been enhanced in the aspects of extension and concurrency.

Features: Non-relational, distributed, open source, horizontally scalable.

Advantages: Easy to expand, read and write faster, cheaper, flexible data model.

Insufficient: No support for SQL support, not rich in features, the current product compared to the relational database is not mature.

All in all, the emergence of NoSQL is closely followed the pace of the times-large data, cloud computing and the birth, and constantly develop, is in a growing. Below a simple look at its more mature product MongoDB simple introduction.

MongoDB's name is taken from the "humongous" (huge) of the middle part, it is evident that the purpose of MongoDB processing a large number of data above. is a scalable, high-performance next-generation database, written in C + + language, designed to provide scalable, high-performance data storage solutions for Web applications.

Mongo db is a good way to implement object-oriented thinking (OO), where each record in Mongo DB is a document object. The biggest advantage of MongoDB is that all data persistence operations require no developer to manually write SQL statements, and the direct invocation of the method makes it easy to implement CRUD operations.

Well, take a look at what the features are, depending on the characteristics we can choose when to use it: high-performance, easy to deploy, easy to use, storage data is very convenient is its main features:

² Free mode, support dynamic query, full index, can easily query the document embedded objects and arrays

² Document-oriented storage for easy storage of object-type data, including document inline objects and arrays

² Efficient data storage, support for binary data and large objects (such as photos and video)

² supports replication and failback; provides master-, master-master-mode data replication and data replication between servers

² Automatic Fragmentation to support cloud-level scalability, support for horizontal database clustering, dynamic addition of additional servers

Applicable scenario:

² a Persistent cache layer that is suitable for the information infrastructure

² is suitable for real-time inserts, updates and queries, and has the replication and high scalability required for application real-time data storage

²mongo's Bson data format is ideal for storing and querying in a documented format

² is suitable for databases made up of dozens of or hundreds of servers. Because Mongo already contains built-in support for the MapReduce engine

Scenario Not applicable:

² requires highly transactional systems

² Traditional Business Intelligence Applications

² Complex cross-document (table) cascading queries

          Comprehensive, we have a macro understanding of Nosql,mongodb, know NoSQL and constantly develop the reasons for the state, MongoDB use range, strengths and weaknesses, This is very important to our understanding of this software, which is related to the choice of technology. Just as we know people, we start with the overall looks, then with the continuous in-depth, in the observation of their detail appearance, behavior, habits and so on, learning a technology is also the case, first understand him, and then in the beginning a little bit of learning technology, and with the increase in the number of use, continuous deepening understanding, continuous sublimation.