一天精通MongoDB数据库

curl -O https://fastdl.mongodb.org/linux/mongodb-linux-x86_64-3.0.6.tgz    # 下载
tar -zxvf mongodb-linux-x86_64-3.0.6.tgz                              # 解压
mv  mongodb-linux-x86_64-3.0.6/ /usr/local/mongodb                    # 将解压包拷贝到指定目录
 
export PATH=<mongodb-install-directory>/bin:$PATH      #<mongodb-install-directory> 为Mongo的安装路径，如本文的 /usr/local/mongodb 
mkdir -p /data/db      #创建数据库目录(启动指定--dbpath)

suoningdeMacBook-Pro:~ suoning$ cat /usr/local/etc/mongod.conf 
systemLog:
  destination: file
  path: /usr/local/var/log/mongodb/mongo.log
  logAppend: true
storage:
  dbPath: /usr/local/var/mongodb
net:
  bindIp: 127.0.0.1
  port: 11811
suoningdeMacBook-Pro:~ suoning$

$ ./mongod 
$ ./mongod --dbpath=/data/db --rest
# 默认端口为：27017
# MongoDB 提供了简单的 HTTP 用户界面。 如果你想启用该功能，需要在启动的时候指定参数 --rest
# MongoDB 的 Web 界面访问端口比服务的端口多1000。如果你的MongoDB运行端口使用默认的27017，你可以在端口号为28017访问web用户界面，即地址为：http://localhost:28017

$ sudo mongo
$ sudo mongo --port 11811
$ sudo mongo -u root -p pwd 127.0.0.1:11811/test

> 
> use admin
switched to db admin
> db
admin
> db.createUser({user:'suoning',pwd:'123456',roles:[{role:'userAdminAnyDatabase',db:'admin'}]})
Successfully added user: {
    "user" : "suoning",
    "roles" : [
        {
            "role" : "userAdminAnyDatabase",
            "db" : "admin"
        }
    ]
}
> exit
bye

suoningdeMacBook-Pro:~ suoning$ cat /usr/local/etc/mongod.conf 
systemLog:
  destination: file
  path: /usr/local/var/log/mongodb/mongo.log
  logAppend: true
storage:
  dbPath: /usr/local/var/mongodb
net:
  bindIp: 127.0.0.1
  port: 11811
security:
   authorization: enabled
suoningdeMacBook-Pro:~ suoning$ 

> 
> show dbs
2017-04-25T08:41:50.126+0800 E QUERY    [thread1] Error: listDatabases failed:{
    "ok" : 0,
    "errmsg" : "not authorized on admin to execute command { listDatabases: 1.0 }",
    "code" : 13,
    "codeName" : "Unauthorized"
} :
_getErrorWithCode@src/mongo/shell/utils.js:25:13
Mongo.prototype.getDBs@src/mongo/shell/mongo.js:62:1
shellHelper.show@src/mongo/shell/utils.js:761:19
shellHelper@src/mongo/shell/utils.js:651:15
@(shellhelp2):1:1
> 
> use admin
switched to db admin
> db.auth('suoning','123456')
1
> show dbs
admin  0.000GB
local  0.000GB
>

> use admin
switched to db admin
> db.auth('suoning','123456')
1
> 
> use mydb
switched to db mydb
> db.createUser({user:'nick',pwd:'123456',roles:[{role:'readWrite',db:'mydb'}]})
Successfully added user: {
    "user" : "nick",
    "roles" : [
        {
            "role" : "readWrite",
            "db" : "mydb"
        }
    ]
}
> 
> db.auth('nick','123456')
1
>

> db.dropUser("nick")
true

> use admin
switched to db admin
> db.auth('suoning','123456')
1
> db.system.users.find()
{ "_id" : "admin.suoning", "user" : "suoning", "db" : "admin", "credentials" : { "SCRAM-SHA-1" : { "iterationCount" : 10000, "salt" : "XXW+MD0TENKSkzk0bM2EGw==", "storedKey" : "iIuv5DpGOksvaFpFOSnAIRSwh+w=", "serverKey" : "ZGA7/Lkjv+RJX3fNANQN9hgBUwY=" } }, "roles" : [ { "role" : "userAdminAnyDatabase", "db" : "admin" } ] }
{ "_id" : "mydb.nick", "user" : "nick", "db" : "mydb", "credentials" : { "SCRAM-SHA-1" : { "iterationCount" : 10000, "salt" : "j71pQs/OR1eRtRa1IT80+w==", "storedKey" : "5hkHmU+FwdENDgGjV0wIbmTAOrQ=", "serverKey" : "Qs+c0gfGNUpwD/ZKgeOackzwNxI=" } }, "roles" : [ { "role" : "readWrite", "db" : "mydb" } ] }
> 

角色说明：
Read：允许用户读取指定数据库
readWrite：允许用户读写指定数据库
dbAdmin：允许用户在指定数据库中执行管理函数，如索引创建、删除，查看统计或访问system.profile
userAdmin：允许用户向system.users集合写入，可以找指定数据库里创建、删除和管理用户
clusterAdmin：只在admin数据库中可用，赋予用户所有分片和复制集相关函数的管理权限。
readAnyDatabase：只在admin数据库中可用，赋予用户所有数据库的读权限
readWriteAnyDatabase：只在admin数据库中可用，赋予用户所有数据库的读写权限
userAdminAnyDatabase：只在admin数据库中可用，赋予用户所有数据库的userAdmin权限
dbAdminAnyDatabase：只在admin数据库中可用，赋予用户所有数据库的dbAdmin权限。
root：只在admin数据库中可用。超级账号，超级权限

> show dbs
admin  0.000GB
local  0.000GB
> 
> use mydb
switched to db mydb
> db
mydb
> 
> db.mydb.insert({"name":"Nick","age":18})
WriteResult({ "nInserted" : 1 })
> 
> show dbs
admin  0.000GB
local  0.000GB
mydb   0.000GB
>
> show tables;
mydb
>

> db.dropUser("nick")
true
> 
> db.createUser({user:'nick',pwd:'123456',roles:[{role:'dbAdmin',db:'mydb'}]})
Successfully added user: {
    "user" : "nick",
    "roles" : [
        {
            "role" : "dbAdmin",
            "db" : "mydb"
        }
    ]
}
> 
> db.auth("nick","123456")
1
> 
> use mydb
switched to db mydb
> db
mydb
> 
> show dbs;
admin  0.000GB
local  0.000GB
mydb   0.000GB
>
> db.dropDatabase()
{ "dropped" : "mydb", "ok" : 1 }
> 
> show dbs;
admin  0.000GB
local  0.000GB
> 

> db;
mydb
> show tables;
mydb
> 
> db.mydb.drop();
true
> show tables;
> 

db.COLLECTION_NAME.insert(document)

> db.createUser({user:'ning',pwd:'123456',roles:[{role:'readWrite',db:'mydb'}]})
Successfully added user: {
    "user" : "ning",
    "roles" : [
        {
            "role" : "readWrite",
            "db" : "mydb"
        }
    ]
}
> 
> db.auth('ning','123456')
1
>

> 
> db.user.insert({'name':'nick','age':18,'girlfriend':['jenny','coco','julia']})
WriteResult({ "nInserted" : 1 })
> 
> show tables
user
>

> 
> vb = ({'sex':'man'});
{ "sex" : "man" }
> db.user.insert(vb);
WriteResult({ "nInserted" : 1 })
>

db.collection.remove(
   <query>,
   <justOne>
)
 
# MongoDB 是 2.6 版本以后的，语法格式如下：
db.collection.remove(
   <query>,
   {
     justOne: <boolean>,
     writeConcern: <document>
   }
)
 
# 参数说明：
query :（可选）删除的文档的条件。
justOne : （可选）如果设为 true 或 1，则只删除一个文档。
writeConcern :（可选）抛出异常的级别。

> db.user.find()
{ "_id" : ObjectId("58fef7d55b9ea92ab29fbd4b"), "name" : "nick", "age" : 18, "girlfriend" : [ "jenny", "coco", "julia" ] }
{ "_id" : ObjectId("58fef9165b9ea92ab29fbd4c"), "sex" : "man" }
> 
> db.user.remove({'sex':'man'})
WriteResult({ "nRemoved" : 1 })
> 
> db.user.find()
{ "_id" : ObjectId("58fef7d55b9ea92ab29fbd4b"), "name" : "nick", "age" : 18, "girlfriend" : [ "jenny", "coco", "julia" ] }
>

>db.COLLECTION_NAME.remove(DELETION_CRITERIA,1)

>db.col.remove({})
>db.col.find()
>

# 只更新一条
> db.user.find()
{ "_id" : ObjectId("58fef7d55b9ea92ab29fbd4b"), "name" : "nick", "age" : 21, "girlfriend" : [ "jenny", "coco", "julia" ] }
{ "_id" : ObjectId("58feffe55b9ea92ab29fbd4d"), "name" : "jenny", "age" : 21 }
> 
> db.user.update({'age':21},{$set:{'age':22}})
WriteResult({ "nMatched" : 1, "nUpserted" : 0, "nModified" : 1 })
> 
> db.user.find()
{ "_id" : ObjectId("58fef7d55b9ea92ab29fbd4b"), "name" : "nick", "age" : 22, "girlfriend" : [ "jenny", "coco", "julia" ] }
{ "_id" : ObjectId("58feffe55b9ea92ab29fbd4d"), "name" : "jenny", "age" : 21 }
> 
 
# 更新多条
> db.user.find()
{ "_id" : ObjectId("58fef7d55b9ea92ab29fbd4b"), "name" : "nick", "age" : 21, "girlfriend" : [ "jenny", "coco", "julia" ] }
{ "_id" : ObjectId("58feffe55b9ea92ab29fbd4d"), "name" : "jenny", "age" : 21 }
> 
> db.user.update({'age':21},{$set:{'age':22}},{multi:true})
WriteResult({ "nMatched" : 2, "nUpserted" : 0, "nModified" : 2 })
> 
> db.user.find()
{ "_id" : ObjectId("58fef7d55b9ea92ab29fbd4b"), "name" : "nick", "age" : 22, "girlfriend" : [ "jenny", "coco", "julia" ] }
{ "_id" : ObjectId("58feffe55b9ea92ab29fbd4d"), "name" : "jenny", "age" : 22 }
>

db.collection.save(
   <document>,
   {
     writeConcern: <document>
   }
)
 
参数说明：
document : 文档数据。
writeConcern :可选，抛出异常的级别。

> db.user.find()
{ "_id" : ObjectId("58fef7d55b9ea92ab29fbd4b"), "name" : "nick", "age" : 22, "girlfriend" : [ "jenny", "coco", "julia" ] }
> 
> db.user.save({ "_id" : ObjectId("58fef7d55b9ea92ab29fbd4b"), "name" : "nick", "age" : 18, "girlfriend" : [ "jenny", "julia" ] })
WriteResult({ "nMatched" : 1, "nUpserted" : 0, "nModified" : 1 })
> 
> db.user.find().pretty()
{
    "_id" : ObjectId("58fef7d55b9ea92ab29fbd4b"),
    "name" : "nick",
    "age" : 18,
    "girlfriend" : [
        "jenny",
        "julia"
    ]
}
>

db.mydb.find(query, projection)
 
query ：可选，使用查询操作符指定查询条件
projection ：可选，使用投影操作符指定返回的键。查询时返回文档中所有键值， 只需省略该参数即可（默认省略）。

pretty() 方法以格式化的方式来显示所有文档。
>db.mydb.find().pretty()

db.col.find({likes : {$lt :200, $gt : 100}}) 

and:
    >db.col.find({key1:value1, key2:value2}).pretty()
or:
    >db.col.find(
       {
          $or: [
             {key1: value1}, {key2:value2}
          ]
       }
    ).pretty()

>db.COLLECTION_NAME.find().limit(NUMBER)

>db.COLLECTION_NAME.find().limit(NUMBER).skip(NUMBER)

>db.COLLECTION_NAME.find().sort({KEY:1})

db.col.find({"title" : {$type : 2}})

>db.COLLECTION_NAME.ensureIndex({KEY:1})
 
语法中 Key 值为你要创建的索引字段，1为指定按升序创建索引，如果你想按降序来创建索引指定为-1即可

复合索引
db.col.ensureIndex({"title":1,"description":-1})

后台执行
通过在创建索引时加background:true 的选项，让创建工作在后台执行
db.values.ensureIndex({open: 1, close: 1}, {background: true})

>db.COLLECTION_NAME.aggregate(AGGREGATE_OPERATION)

> db.mycol.aggregate([{$group : {_id : "$by_user", num_tutorial : {$sum : 1}}}])
 
以上实例类似sql语句： select by_user, count(*) from mycol group by by_user
我们通过字段by_user字段对数据进行分组，并计算by_user字段相同值的总和。

db.article.aggregate(
    { $project : {
        title : 1 ,
        author : 1 ,
    }}
 );
这样的话结果中就只还有_id,tilte和author三个字段了，默认情况下_id字段是被包含的，如果要想不包含_id话可以这样:
db.article.aggregate(
    { $project : {
        _id : 0 ,
        title : 1 ,
        author : 1
    }});

db.articles.aggregate( [
                        { $match : { score : { $gt : 70, $lte : 90 } } },
                        { $group: { _id: null, count: { $sum: 1 } } }
                       ] );
$match用于获取分数大于70小于或等于90记录，然后将符合条件的记录送到下一阶段$group管道操作符进行处理。

db.article.aggregate(
    { $skip : 5 });
经过$skip管道操作符处理后，前五个文档被"过滤"掉。

> db.user.find({"name":"nick"}).explain();
> db.user.find({"name":"nick"}).explain(true);

executionStats.executionSuccess
是否执行成功
 
executionStats.nReturned
查询的返回条数
 
executionStats.executionTimeMillis
整体执行时间
 
executionStats.totalKeysExamined
索引扫描次数
 
executionStats.totalDocsExamined
document扫描次数

如下查询指定了使用 naem 和 age 索引字段来查询：
> db.user.find({"name":"nick","age":18}).hint({"name":1,"age":1});