Distributed Document Storage Database MongoDB

MongoDB Detailed Introduction

MongoDB is a product between a relational database and a non-relational database, and is the most versatile and most like relational database in a non-relational database. The data structure he 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.

Overall architecture:

Internal architecture:

It is characterized by high performance, easy to deploy, easy to use, and easy to store data. The main features are:

• For collection storage, easy to store data for object types.

• Mode of freedom.

• Supports dynamic queries.

• Supports full indexes, including internal objects.

• Support Queries.

• Supports replication and recovery.

• Use efficient binary data storage, including large objects such as video.

• Automatically process fragmentation to support scalability at the cloud level

• Supports multiple languages such as ruby,python,java,c++,php.

• File storage format is Bson (an extension of JSON)

• Accessible over the network

The so-called "set-oriented" (collenction-orented), meaning that data is grouped in a dataset, is called a collection (collenction). Each collection has a unique identifying name in the database and can contain an unlimited number of documents. The concept of a collection is similar to a table in a relational database (RDBMS), unlike it does not need to define any schema (schema).
Mode Freedom (schema-free) means that for files stored in a MongoDB database, we do not need to know any of its structure definitions. If necessary, you can store files of different structures in the same database.
The documents stored in the collection are stored in the form of key-value pairs. The key is used to uniquely identify a document as a string type, whereas a value can be a complex file type in each. We call this storage form Bson (Binary serialized dOcument Format).

The MongoDB server can run on Linux, Windows or OS X platforms, supports 32-bit and 64-bit applications, and the default port is 27017. Recommended to run on 64-bit platforms because MongoDB

The maximum file size supported when running in 32-bit mode is 2GB.

MongoDB stores the data in a file (the default path is:/data/db), which is managed using a memory-mapped file for increased efficiency.

Distributed Document Storage Database MongoDB