MongoDB Getting started must read

I. Overview

　　MongoDB is a database open source project based on distributed file storage.

Written in the C + + language , it is designed to provide a high-performance, sustainable data storage solution for WEB applications.

MongoDB is a product between a relational database and a non-relational database.

The data structure it supports is very loose and is a json - like bjson format, so you can store more complex data types.

Mongo's biggest feature is that the query language he supports is very powerful, and its syntax is a bit like an object-oriented query language that almost implements most of the functionality of a relational database single-table query, and also supports indexing of data.  

　　MongoDB mainly solves the problem of access efficiency of massive data.

According to official documents, when the amount of data reached 50GB above, Span style= "Font-family:consolas;" >mongo mysql Span style= "font-family: the song Body;" The 10 mongo 0.5 1.5 Read and write requests.

  because mongodb mostly support massive data storage, so mongo also comes with an excellent distributed file system gridfs can support a huge amount of data storage, but I also see some comments that gridfs poor performance, to be verified.  

  last due to mongo mongodb to replace the mysql to implement not particularly complex Span style= "Font-family:consolas;" >web Application, for example why we  Migrated from mysql to mongodb is a real slave. mysql migrate to mongodb mongo above , the speed of data query has been greatly improved.  

summed up,monggdb is characterized by high performance, easy to deploy, easy to use, storage data is very convenient.

Second, The advantages of MongoDB

(1) high performance, very fast ( If you have enough memory )

(2) no fixed table structure, no data migration in order to modify the table structure

(3) the query language is simple and easy to get started

(4) use sharding to achieve horizontal scaling

(5) easy to deploy

Third, using MongoDB, you have to remember the following points:

MongoDB assumes you have large disk space

MongoDB assumes that your memory is also greater than putting down your hot data

MongoDB assumes that you are deployed on the system ( 2G limit, trial can also )

MongoDB assumes that your system is Little-endian .

MongoDB assumes you have multiple machines ( not focused on single machine reliability )

MongoDB assumes you want to use security for performance, while allowing you to use performance for security

MongoDB is not very good at the following areas

Not very stable, especially auto-sharding , There are still a lot of problems.

does not support SQL, which means that many of your tools through the SQL interface no longer apply

Persistent,MongoDB stand-alone reliability is not good, downtime may be lost for a period of time data

There are fewer related documents and the new features have this problem

It is also one of the problems of new function that the related talents are difficult to find.

MongoDB Getting started must read