Introduction to mongodb chapter 01 introduction to mongodb

MongoDB

MongoDB It's open source 、 Cross platform 、 Distributed document database , Belong to NoSQL（Not Only SQL） A kind of database .

Simple and easy to use

MongoDB It's a document oriented database , Using document （document） Object stores data , This approach is better than relational databases （RDBMS） The data row format in is more flexible .

Documents can support the representation of complex hierarchical relationships in a single record .

MongoDB No predefined schema structure is required （schema）, You can add or delete fields in the document more easily and quickly .

Scalable

As the volume of data grows , We will face the challenge of scalability . Generally speaking , There are two ways to expand ：

• Vertical expansion （Scaling up）, Upgrade server resources （CPU、RAM etc. ）.
• Horizontal scaling （Scaling out）, Add more servers to the cluster . This is more economical than vertical expansion 、 Better scalability , The drawback is that management is more complex .

MongoDB Born with horizontal scalability .

MongoDB Data can be distributed and stored in multiple servers , At the same time, it can automatically manage load balancing across nodes , Route data operations to the appropriate server . The following figure illustrates MongoDB Use sharding Schematic diagram of horizontal expansion by slices ：

Rich in functions

As a database management system ,MongoDB Support data insertion 、 to update 、 Delete and query . besides ,MongoDB The following functions are also provided ：

• Indexes
• polymerization
• Specify the type of set and index
• File store

We will introduce these functions in detail in the following tutorials .

High performance

MongoDB Provides high-performance data storage , for example , The embedded data model can reduce I/O operation , Indexing can speed up queries .

MongoDB The idea is to create an extensible 、 Flexible and high-performance full-featured database .

MongoDB edition

MongoDB Three different versions are available ： Community Edition 、 Enterprise edition and cloud database （Atlas）.

MongoDB Community Edition

MongoDB The Community Edition is free to use , Support Windows、Linux as well as macOS platform .

MongoDB The community edition uses (SSPL) license , It means that if we will MongoDB As a public service for others to use , The software code that supports this service must be open source , For example, tools to manage or monitor the service . otherwise , We need to buy enterprise edition .

If we use MongoDB Community Edition as a component of the application , Not the final product , Free to use .

MongoDB Enterprise Edition

MongoDB The enterprise version is MongoDB Commercial version of , It's also MongoDB Part of the enterprise premium subscription .

MongoDB The enterprise edition provides many features that the community edition does not support , for example ：

• Memory （In-Memory） Storage engine
• Audit function
• Kerberos authentication
• LDAP Proxy authentication and LDAP to grant authorization
• Static encryption

MongoDB Atlas

MongoDB Atlas Is a global cloud database service . It is a database as a service （database as a service）, It allows us to focus on application development , Instead of managing the database .

MongoDB Atlas Support various common cloud platforms , Include AWS、Azure as well as GCP, Alibaba cloud in China 、 Tencent cloud also provides corresponding services .MongoDB Atlas It provides individuals with a free database service for learning .