Mongodb Study Notes 01 and mongodb Study Notes

Mongodb Study Notes 01 and mongodb Study Notes
Mongodb Overview

Mongodb is a document-type NoSQL database that stores bson-> json binary. The internal execution engine is a js interpreter that stores documents into a bson structure and converts them to js objects during query. And can be operated through js syntax.

Comparison between mongodb and traditional databases

Traditional DatabasesIs a structured database with the same number of Columns

Document DatabaseIn document units
For example:

{    id:1,    name: "billvsme",    age:21,}

{    id:2,    name: "zhangshan",    phone:12313,    address:23424,}

Can all exist under a table

Document DatabaseThe biggest feature is "no structure". Each document in the table can have its own unique attributes and values.

Column: Comment reply, score, at least multiple tables in the traditional database, the Association is complex, and a document in the document database can be completed

{Title: 'xxxx' comment: [{connent: 'You wrote well !!! ', Reply: ['comments are good', 'Write is good ']}, {connent:' not good at writing ~~ ', Reply: ['approval', 'strongly approval']}

Mongodb Installation

Download the package directly and decompress it to run it.
Https://fastdl.mongodb.org/linux/mongodb-linux-x86_64-3.0.4.tgz

Mongodb running mongodb file structure

• Bsondump binary Export
• Mongo client (equivalent to mysql)
• Mongod server (equivalent to mysqld)
• Mongodump overall Database Export
• Mongoexport export is easy to recognize json or csv documents
• Mongorestore import database
• Mongos router (used for sharding)

Start mongod

mongod --dbpath /path/to/database --logpath  /path/to/logfile --fork  --port 27017

• -Dbpath: database storage path
• -Logpath: Log File Path
• -Port: 27017 by default
• -Fork background running

Test

Enter./mongo directly to mongo.

• Show dbs
• Use database to enter the database
• Show tables/collections View table
• Db. help () help