Features of the main MongoDB

MongoDB Introduction (features, advantages, Principles) Description: MongoDB is a database based on distributed file storage. Written in the C+ + language. Designed to provide scalable, high-performance data storage solutions for Web applications. Features: High performance, easy to deploy, easy to use, easy to store data. Main features are: Ø for collection storage, easy to store object type of data Ø mode free Ø Support Dynamic query Ø Support full index, including internal object Ø support query Ø Support replication and failback ø using efficient binary data storage, including large objects (such as video, etc.) Ø Automatic processing of fragments, To support the scalability of cloud computing level Ø support RUBY,PYTHON,JAVA,C+ +, PHP and other languages Ø file storage format for Bson (a JSON extension) Ø can be accessed through the network using the principle of so-called "set-oriented" (Collenction -oriented), meaning that data is grouped in a dataset, 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). Schema 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 variety of complex file types. We call this storage form Bson (Binary JSON).

The MongoDB document database, which stores the document (Bson->json binary).

Features: Internal execution engine for JS interpreter, the document is stored as Bson structure, in the query, converted to JS object, and can be manipulated by the familiar JS syntax.

MONGO is the biggest difference compared to traditional databases:

Traditional database: Structured data, after the table structure, the content of each row must be consistent with the table structure, that is, the number of columns, the type is the same.

MONGO document database: Each document under a table can have its own unique structure (JSON objects can have their own unique properties and values)

Idea: If there is a film, review, comment on the reply, reply to the score

In a traditional database, at least 4 tables, the correlation degree is very complex.

In the document database, you can do it with 1 documents. Reflects the anti-normalization of the document-type database.

{

Fiim: ' Tianlong eight '

comment:[

{content: ' Wong Kar-wai's cinematic style ',

reply:[' support ', ' good ']

}

]

}

Features of the main MongoDB