MongoDB基本操作

1. 进入mongo环境

 mongo

 [root@slave2 ~]# mongo

MongoDB shell version v3.4.16

connecting to: mongodb://127.0.0.1:27017

MongoDB server version: 3.4.16

Server has startup warnings: 

2018-07-20T17:53:38.109+0800 I CONTROL  [initandlisten] 

2018-07-20T17:53:38.109+0800 I CONTROL  [initandlisten] ** WARNING: Access control is not enabled for the database.

2018-07-20T17:53:38.109+0800 I CONTROL  [initandlisten] **          Read and write access to data and configuration is unrestricted.

2018-07-20T17:53:38.109+0800 I CONTROL  [initandlisten] 

2018-07-20T17:53:38.109+0800 I CONTROL  [initandlisten] 

2018-07-20T17:53:38.109+0800 I CONTROL  [initandlisten] ** WARNING: /sys/kernel/mm/transparent_hugepage/enabled is 'always'.

2018-07-20T17:53:38.109+0800 I CONTROL  [initandlisten] **        We suggest setting it to 'never'

2018-07-20T17:53:38.109+0800 I CONTROL  [initandlisten] 

2018-07-20T17:53:38.109+0800 I CONTROL  [initandlisten] ** WARNING: /sys/kernel/mm/transparent_hugepage/defrag is 'always'.

2018-07-20T17:53:38.109+0800 I CONTROL  [initandlisten] **        We suggest setting it to 'never'

2018-07-20T17:53:38.109+0800 I CONTROL  [initandlisten] 

>

2.查询所有数据库

show dbs;  

> show dbs 

admin  0.000GB

local  0.000GB 

3.创建或者切换库（如果数据库不存在，则创建数据库，否则切换到指定数据库）

use mydb； 

> use mydb

switched to db mydb

> show dbs

admin  0.000GB

local  0.000GB

可以看到，我们刚创建的数据库 mydb并不在数据库的列表中， 要显示它，我们需要向 mydb数据库插入一些数据。

4.创建集合 

> db.createCollection("log")

{ "ok" : 1 }

> show dbs

admin  0.000GB

local  0.000GB

mydb   0.000GB

5. 插入数据 （如果插入时集合不存在，则包括创建集合和插入数据两个动作）及更新

> db.logdata.insert({name:'zhangsan', age:'25'});

WriteResult({ "nInserted" : 1 } 

> db.logdata.insert({'_id': 'terrywang', 'super_admin': true}) 

WriteResult({ "nInserted" : 1 }) 

> db.logdata.find({'_id':'terrywang'})

{ "_id" : "terrywang", "super_admin" : true } 

> db.logdata.update({'_id': 'terrywang'}, {$set: {'super_admin': false}})

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

> db.logdata.find({"_id":"terrywang"})

{ "_id" : "terrywang", "super_admin" : false } 

6.查看集合内容

> db.logdata.find()

{ "_id" : ObjectId("5b529ef8bfde59a50f5e5397"), "name" : "lisi", "age" : "30" }

{ "_id" : "terrywang", "super_admin" : false }

> db.logdata.findOne({'_id':'terrywang'})

{ "_id" : "terrywang", "super_admin" : true } 

7.按条件筛选

> db.logdata.find({"name":"zhangsan"});

{ "_id" : ObjectId("5b529e14bfde59a50f5e5396"), "name" : "zhangsan", "age" : "25" }

7.1 正则查找 

> db.logdata.find({"_id":/e*/i})

{ "_id" : "terrywang", "super_admin" : false }

   i表明是否是case-insensitive，有i则表示忽略大小写 

7.2 只筛选到某一列 

> db.logdata.find({},{D:1})

{ "_id" : ObjectId("5b529ad3aea13d710cc622d5") }  

7.3 查询去掉后的当前聚集集合中的某列的重复数据 

> db.logdata.find()

{ "_id" : ObjectId("5b529ad3aea13d710cc622d5"), "name" : "zhangsan", "age" : "25" }

> db.logdata.insert({"name":"Terry","age":"35"})

WriteResult({ "nInserted" : 1 })

> db.logdata.distinct("name")

[ "zhangsan", "Terry" ]

> db.logdata.insert({"name":"Terry","age":"35"})

WriteResult({ "nInserted" : 1 })

> db.logdata.distinct("name")

[ "zhangsan", "Terry" ]

 会过滤掉name中的相同数据 。相当于：select distict name from logdata;

7.4  查询age = "35"的记录

> db.logdata.find({"age": "35"});

{ "_id" : ObjectId("5b52f18c66401eea4b0c151a"), "name" : "Terry", "age" : "35" }

{ "_id" : ObjectId("5b52f1a066401eea4b0c151b"), "name" : "Terry", "age" : "35" }

 相当于 select * from logdata where age = “35”;

7.5 查询age > “26”的记录  

> db.logdata.find({age: {$gt: "26"}}); 

{ "_id" : ObjectId("5b52f18c66401eea4b0c151a"), "name" : "Terry", "age" : "35" }

{ "_id" : ObjectId("5b52f1a066401eea4b0c151b"), "name" : "Terry", "age" : "35" }

7.6 查询age < “26”的记录 

> db.logdata.find({age:{$lt:"26"}}); 

{ "_id" : ObjectId("5b529ad3aea13d710cc622d5"), "name" : "zhangsan", "age" : "25" }

7.6 查询age < “35”的记录 

> db.logdata.find({age: {$lte: "35"}}); 

{ "_id" : ObjectId("5b529ad3aea13d710cc622d5"), "name" : "zhangsan", "age" : "25" }

{ "_id" : ObjectId("5b52f18c66401eea4b0c151a"), "name" : "Terry", "age" : "35" }

{ "_id" : ObjectId("5b52f1a066401eea4b0c151b"), "name" : "Terry", "age" : "35" }

 7.7 查询age >= 26并且 age <= 36

> db.logdata.find({age: {$gte: "26", $lte: "35"}}); 

{ "_id" : ObjectId("5b52f18c66401eea4b0c151a"), "name" : "Terry", "age" : "35" }

{ "_id" : ObjectId("5b52f1a066401eea4b0c151b"), "name" : "Terry", "age" : "35" }

 7.8 查询name中包含 Ter的数据

> db.logdata.find({name: /Ter/});

{ "_id" : ObjectId("5b52f18c66401eea4b0c151a"), "name" : "Terry", "age" : "35" }

{ "_id" : ObjectId("5b52f1a066401eea4b0c151b"), "name" : "Terry", "age" : "35" }

7.9 查询name中以Ter开头的  

> db.logdata.find({name: /^Ter/});   

{ "_id" : ObjectId("5b52f18c66401eea4b0c151a"), "name" : "Terry", "age" : "35" }

{ "_id" : ObjectId("5b52f1a066401eea4b0c151b"), "name" : "Terry", "age" : "35" }

 7.10 显示指定列

> db.logdata.find({}, {name: 1, age: 1});  

{ "_id" : ObjectId("5b529ad3aea13d710cc622d5"), "name" : "zhangsan", "age" : "25" }

{ "_id" : ObjectId("5b52f18c66401eea4b0c151a"), "name" : "Terry", "age" : "35" }

{ "_id" : ObjectId("5b52f1a066401eea4b0c151b"), "name" : "Terry", "age" : "35" }

> db.logdata.find({}, {age: 1});

{ "_id" : ObjectId("5b529ad3aea13d710cc622d5"), "age" : "25" }

{ "_id" : ObjectId("5b52f18c66401eea4b0c151a"), "age" : "35" }

{ "_id" : ObjectId("5b52f1a066401eea4b0c151b"), "age" : "35" }

 7.11 按年龄升降序  

> db.logdata.find().sort({age: 1}) 

{ "_id" : ObjectId("5b529ad3aea13d710cc622d5"), "name" : "zhangsan", "age" : "25" }

{ "_id" : ObjectId("5b52f18c66401eea4b0c151a"), "name" : "Terry", "age" : "35" }

{ "_id" : ObjectId("5b52f1a066401eea4b0c151b"), "name" : "Terry", "age" : "35" }

> db.logdata.find().sort({age: -1});

{ "_id" : ObjectId("5b52f18c66401eea4b0c151a"), "name" : "Terry", "age" : "35" }

{ "_id" : ObjectId("5b52f1a066401eea4b0c151b"), "name" : "Terry", "age" : "35" }

{ "_id" : ObjectId("5b529ad3aea13d710cc622d5"), "name" : "zhangsan", "age" : "25" }

7.12 查询前2条 

> db.logdata.find().limit(2) 

{ "_id" : ObjectId("5b529ad3aea13d710cc622d5"), "name" : "zhangsan", "age" : "25" }

{ "_id" : ObjectId("5b52f18c66401eea4b0c151a"), "name" : "Terry", "age" : "35" }

7.13 查询1条以后的数据

> db.logdata.find().skip(1) 

{ "_id" : ObjectId("5b52f18c66401eea4b0c151a"), "name" : "Terry", "age" : "35" }

{ "_id" : ObjectId("5b52f1a066401eea4b0c151b"), "name" : "Terry", "age" : "35" }

7.14 查询在1-2之间的数据  

> db.logdata.find().limit(2).skip(1) 

{ "_id" : ObjectId("5b52f18c66401eea4b0c151a"), "name" : "Terry", "age" : "35" }

{ "_id" : ObjectId("5b52f1a066401eea4b0c151b"), "name" : "Terry", "age" : "35" }

7.15 年龄等于“25”或者等于“35”

> db.logdata.find({$or: [{age: "25"}, {age: "35"}]})  

{ "_id" : ObjectId("5b529ad3aea13d710cc622d5"), "name" : "zhangsan", "age" : "25" }

{ "_id" : ObjectId("5b52f18c66401eea4b0c151a"), "name" : "Terry", "age" : "35" }

{ "_id" : ObjectId("5b52f1a066401eea4b0c151b"), "name" : "Terry", "age" : "35" } 

 8.删除文档

先插入一个文档 

> db.logdata.insert({name:'lisi', age:'30'});

WriteResult({ "nInserted" : 1 })

> db.logdata.find()

{ "_id" : ObjectId("5b529e14bfde59a50f5e5396"), "name" : "zhangsan", "age" : "25" }

{ "_id" : ObjectId("5b529ef8bfde59a50f5e5397"), "name" : "lisi", "age" : "30" } 

删除一个文档

> db.logdata.remove({"name":"zhangsan"}) 

WriteResult({ "nRemoved" : 1 })

> db.logdata.find()

{ "_id" : ObjectId("5b529ef8bfde59a50f5e5397"), "name" : "lisi", "age" : "30" }

 9.显示集合 

> show tables;

log

logdata

10.显示集合中文档数

> db.logdata.find()

{ "_id" : ObjectId("5b529ef8bfde59a50f5e5397"), "name" : "lisi", "age" : "30" }

{ "_id" : "terrywang", "super_admin" : false }

> db.logdata.count()

2

11.查看集合索引

> db.logdata.getIndex()

2018-07-21T11:42:09.337+0800 E QUERY    [thread1] TypeError: db.logdata.getIndex is not a function :

@(shell):1:1

> db.logdata.getIndexes()

[

        {

                "v" : 2,

                "key" : {

                        "_id" : 1

                },

                "name" : "_id_",

                "ns" : "mydb.logdata"

        }

] 

12.删除表 

> db.logdata.drop() 

true

> show tables;

log

test

> db.test.drop()

true

> show tables

log

11.删除库

进入要删除的库， 执行db.dropDatabase();

> show dbs;

admin  0.000GB

local  0.000GB

mydb   0.000GB

mydb2  0.000GB

test   0.000GB

> use test;

switched to db test

> db.dropDatabase();

{ "dropped" : "test", "ok" : 1 }

> show dbs;

admin  0.000GB

local  0.000GB

mydb   0.000GB

mydb2  0.000GB

12.查看当前的数据库 

> use mydb; 

switched to db mydb

> db.getName()

mydb

 13. 显示当前db状态 

> db.stats() 

{

        "db" : "mydb",

        "collections" : 2,

        "views" : 0,

        "objects" : 1,

        "avgObjSize" : 53,

        "dataSize" : 53,

        "storageSize" : 20480,

        "numExtents" : 0,

        "indexes" : 2,

        "indexSize" : 20480,

        "ok" : 1

}

14.显示当前db版本 

> db.version() 

3.4.16

 15. 查看当前db的链接机器地址

> db.getMongo()

connection to 127.0.0.1:27017