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HomeDatabaseMysql Tutorial【MongoDB数据库】MongoDB命令入门初探

【MongoDB数据库】MongoDB命令入门初探

Jun 07, 2016 pm 03:56 PM
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MongoDB是一款NoSql数据库,使用了“面向集合”(Collection-Oriented)原理,意思是数据被分组存储在数据集中,被称为一个集合(Collection)。每个集合(Collection)在数据库中都有一个唯一的标识名,并且可以包含无限数目的对象(BasicDBObject)。 集合(Co

MongoDB是一款NoSql数据库,使用了“面向集合”(Collection-Oriented)原理,意思是数据被分组存储在数据集中,被称为一个集合(Collection)。每个集合(Collection)在数据库中都有一个唯一的标识名,并且可以包含无限数目的对象(BasicDBObject)。

集合(Collection)的概念类似关系型数据库(RDBMS)里的表(table),对象(BasicDBObject)的概念类似于RDBMS中表的一条数据,关系数据库里插入一条数据等价于在MongoDB的Collection中添加一个BasicDBObject。

喜欢Java的人会很快喜欢上MongoDB的,因为其面向对象的操作让人眼前一亮。上一篇我们介绍了MongoDB的安装与配置过程,本篇blog以通俗简洁的方式介绍了MongoDB 入门级命令。

1、进入mongodb shell

在控制面板中开启MongoDB服务,同时使用mongo命令连接已经启动的MongoDB server,进入mongodb shell,如下图所示:

2、显示当前数据库

>db

test

3、显示所有数据库

>show dbs

admin (empty)
andyDB 0.078GB
local 0.078GB

4、切换数据库(如果该数据库不存在,则创建一个数据库)
>use andyDB

switched to db andyDB

5、显示所有的表(集合Collection)

>show collections

system.indexes

6、创建一个表person,并初始化数据

>db.person.insert({name:"andy",age:25})

WriteResult({ "nInserted" : 1 })

7、插入一条记录

>db.person.save({name:"jack",age:50})

WriteResult({ "nInserted" : 1 })

8、查询所有记录

>db.person.find()

{ "_id" : ObjectId("537761762c82bf816b34e6ce"), "name" : "andy", "age" : 25 }
{ "_id" : ObjectId("537761da2c82bf816b34e6cf"), "name" : "jack", "age" : 50 }

9、查询某一条记录

> db.person.find({name:"jack"})

{ "_id" : ObjectId("537761da2c82bf816b34e6cf"), "name" : "jack", "age" : 50 }

> db.person.find({$where:"this.name.length

{ "_id" : ObjectId("537761762c82bf816b34e6ce"), "name" : "andy", "age" : 25 }

{ "_id" : ObjectId("537761da2c82bf816b34e6cf"), "name" : "jack", "age" : 50 }

10、更新一条记录

> db.person.update({name:"andy"},{$set:{age:100}})

WriteResult({ "nMatched" : 1, "nUpserted" : 0, "nModified" : 1 })

> db.person.find({name:"andy"})

{ "_id" : ObjectId("537761762c82bf816b34e6ce"), "name" : "andy", "age" : 100 }

11、删除一条记录

> db.person.remove({name:"andy"})

WriteResult({ "nRemoved" : 1 })

> db.person.find()

{ "_id" : ObjectId("537761da2c82bf816b34e6cf"), "name" : "jack", "age" : 50 }

>db.person.remove()//删除表中的所有记录

>db.person.drop()//删除表

12、查看帮助命令

1)db.help() 显示关于db的帮助命令

>db.help()

2)db.collection.help()显示关于Collection的帮助命令

>db.person.help()

3)db.collection.function.help()显示关于Collection方法的帮助命令

> db.person.function.help()

13、参考

MongoDB Hello World Example(推荐)

Getting Started with MongoDB

14、你可能感兴趣

【MongoDB数据库】如何安装、配置MongoDB

【MongoDB数据库】Java MongoDB CRUD Example

转载请注明出处:http://blog.csdn.net/andie_guo/article/details/26095367,谢谢!

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