MongoDB

cat > /etc/yum.repos.d/mongodb-org-6.0.repo << EOF
[mongodb-org-6.0]
name=MongoDB Repository
baseurl=https://repo.mongodb.org/yum/redhat/$releasever/mongodb-org/6.0/x86_64/
gpgcheck=1
enabled=1
gpgkey=https://www.mongodb.org/static/pgp/server-6.0.asc
EOF

#安装最新版
sudo yum install -y mongodb-org

#安装指定版本
sudo yum install -y mongodb-org-6.0.3 mongodb-org-database-6.0.3 mongodb-org-server-6.0.3 mongodb-mongosh-6.0.3 mongodb-org-mongos-6.0.3 mongodb-org-tools-6.0.3

#导入公钥
wget -qO - https://www.mongodb.org/static/pgp/server-6.0.asc | sudo apt-key add -

#配置仓库文件
#基于Ubuntu20.04
echo "deb [ arch=amd64,arm64 ] https://repo.mongodb.org/apt/ubuntu focal/mongodb-org/6.0 multiverse" | sudo tee /etc/apt/sources.list.d/mongodb-org-6.0.list

sudo apt-get update

sudo apt-get install -y mongodb-org

sudo apt-get install -y mongodb-org=5.0.2 mongodb-org-database=5.0.2 mongodb-org-server=5.0.2 mongodb-org-shell=5.0.2 mongodb-org-mongos=5.0.2 mongodb-org-tools=5.0.2

#Red Hat/CentOS：
yum install libcurl openssl

#Ubuntu 18.04 LTS ("Bionic")/Debian 10 "Buster"：
sudo apt-get install libcurl4 openssl

#Ubuntu 16.04 LTS ("Xenial")/Debian 9 "Stretch"：
sudo apt-get install libcurl3 openssl

https://docs.mongodb.com/manual/tutorial/transparent-huge-pages/

Transparent Huge Pages (THP) is a Linux memory management system that
reduces the overhead of Translation Lookaside Buffer (TLB) lookups on
machines with large amounts of memory by using larger memory pages.
However, database workloads often perform poorly with THP enabled, because
they tend to have sparse rather than contiguous memory access patterns. When
running MongoDB on Linux, THP should be disabled for best performance.

https://docs.mongodb.com/manual/tutorial/install-mongodb-on-red-hat/
Starting in MongoDB 4.4, a startup error is generated if the ulimit valuefor number of open files is under 64000.

cat >> /etc/rc.local <<EOF
echo never > /sys/kernel/mm/transparent hugepage/enabled
EOF
chmod +x /etc/rc.local

[root@ubuntu2004 ~]#cat install_mongodb.sh 
#!/bin/bash
#
#********************************************************************
#Author:            shuhong
#QQ:                985347841
#Date:              2022-12-25
#FileName:          install_mongodb.sh
#URL:               hhhhh
#Description:       The test script
#Copyright (C):     2022 All rights reserved
#********************************************************************

#MONGODB_VERSOIN=rhel80-5.0.3
#MONGODB_VERSOIN=rhel70-5.0.3
#MONGODB_VERSOIN=ubuntu1804-5.0.3
#MONGODB_VERSOIN=ubuntu1804-4.4.4
MONGODB_VERSOIN=ubuntu2004-6.0.3


MONGODB_FILE=mongodb-linux-x86_64-${MONGODB_VERSOIN}.tgz
#MONGODB_FILE=mongodb-linux-x86_64-ubuntu1804-4.4.4.tgz
URL=https://fastdl.mongodb.org/linux/$MONGODB_FILE
MONGODB_DIR=/mongodb
INSTALL_DIR=/usr/local
PORT=27017
MY_IP=hostname -I|awk '{print $1}'

. /etc/os-release

color () {
    RES_COL=60
    MOVE_TO_COL="echo -en \\033[${RES_COL}G"
    SETCOLOR_SUCCESS="echo -en \\033[1;32m"
    SETCOLOR_FAILURE="echo -en \\033[1;31m"
    SETCOLOR_WARNING="echo -en \\033[1;33m"
    SETCOLOR_NORMAL="echo -en \E[0m"
    echo -n "$1" && $MOVE_TO_COL
    echo -n "["
    if [ $2 = "success" -o $2 = "0" ] ;then
        ${SETCOLOR_SUCCESS}
        echo -n $"  OK  "    
    elif [ $2 = "failure" -o $2 = "1"  ] ;then 
        ${SETCOLOR_FAILURE}
        echo -n $"FAILED"
    else
        ${SETCOLOR_WARNING}
        echo -n $"WARNING"
    fi
    ${SETCOLOR_NORMAL}
    echo -n "]"
    echo 
}


system_prepare () {
    [ -e $MONGODB_DIR -o -e $INSTALL_DIR/mongodb ] && { color  "MongoDB 数据库已安装!" 1;exit; }
    if  [ $ID = "centos" -o $ID = "rocky" ];then
        rpm -q curl  &> /dev/null || yum install -y -q curl
    elif [ $ID = "ubuntu" ];then
        dpkg -l curl &> /dev/null || apt -y install curl
    else
        color  '不支持当前操作系统!' 1
        exit
    fi
    if [ -e /etc/rc.local ];then
        echo "echo never > /sys/kernel/mm/transparent hugepage/enabled" >> /etc/rc.local
    else
        cat > /etc/rc.local <<EOF
#!/bin/bash
echo never > /sys/kernel/mm/transparent hugepage/enabled
EOF
    fi
    chmod +x /etc/rc.local   
}

mongodb_file_prepare () {
    if [ ! -e $MONGODB_FILE ];then
        curl -O  $URL || { color  "MongoDB 数据库文件下载失败" 1; exit; } 
    fi
}

install_mongodb () {
    id mongod &> /dev/null || useradd -m -s /bin/bash mongod
    tar xf $MONGODB_FILE -C $INSTALL_DIR
    ln -s $INSTALL_DIR/mongodb-linux-x86_64-${MONGODB_VERSOIN} $INSTALL_DIR/mongodb
    #mongod --dbpath $db_dir --bind_ip_all --port $PORT --logpath $db_dir/mongod.log --fork
}

config_mongodb(){
    echo PATH=$INSTALL_DIR/mongodb/bin/:'$PATH' > /etc/profile.d/mongodb.sh
    . /etc/profile.d/mongodb.sh
    mkdir -p $MONGODB_DIR/{conf,data,log}
    cat > $MONGODB_DIR/conf/mongo.conf <<EOF
systemLog:
  destination: file
  path: "$MONGODB_DIR/log/mongodb.log"
  logAppend: true

storage:
  dbPath: "$MONGODB_DIR/data/"
  journal:
    enabled: true
 
processManagement:
  fork: true

net:
  port: 27017
  bindIp: 0.0.0.0
EOF
    chown -R  mongod.mongod $MONGODB_DIR/
    cat > /lib/systemd/system/mongod.service <<EOF
[Unit]
Description=mongodb
After=network.target remote-fs.target nss-lookup.target

[Service]
Type=forking
User=mongod
Group=mongod
ExecStart=$INSTALL_DIR/mongodb/bin/mongod --config $MONGODB_DIR/conf/mongo.conf
ExecReload=/bin/kill -s HUP \$MAINPID
ExecStop=$INSTALL_DIR/bin/mongod --config $MONGODB/conf/mongo.conf --shutdown
PrivateTmp=true
# file size
LimitFSIZE=infinity
# cpu time
LimitCPU=infinity
# virtual memory size
LimitAS=infinity
# open files
LimitNOFILE=64000
# processes/threads
LimitNPROC=64000
# locked memory
LimitMEMLOCK=infinity
# total threads (user+kernel)
TasksMax=infinity
TasksAccounting=false
# Recommended limits for mongod as specified in
# https://docs.mongodb.com/manual/reference/ulimit/#recommended-ulimit-settings

[Install]
WantedBy=multi-user.target
EOF
    systemctl daemon-reload
    systemctl enable --now  mongod &>/dev/null
}

start_mongodb() { 
    systemctl is-active mongod.service &>/dev/null
    if [ $?  -eq 0 ];then  
        echo 
        color "MongoDB 安装完成!" 0
    else
        color "MongoDB 安装失败!" 1
        exit
    fi 
}

system_prepare 
mongodb_file_prepare
install_mongodb
config_mongodb
start_mongodb

#安装一个客户端
[root@ubuntu2004 ~]#apt -y install mongodb-clients 

[root@ubuntu2004 ~]#apt -y install mongodb-clients 

[root@ubuntu2004 ~]#mongo
MongoDB shell version v3.6.8
connecting to: mongodb://127.0.0.1:27017
Implicit session: session { "id" : UUID("d3690a18-314f-4faf-b5b2-a960352aa01b") }
MongoDB server version: 6.0.3
WARNING: shell and server versions do not match
Server has startup warnings: 
{"t":{"$date":"2022-12-25T11:04:18.124+08:00"},"s":"I",  "c":"STORAGE",  "id":22297,   "ctx":"initandlisten","msg":"Using the XFS filesystem is strongly recommended with the WiredTiger storage engine. See http://dochub.mongodb.org/core/prodnotes-filesystem","tags":["startupWarnings"]}

{"t":{"$date":"2022-12-25T11:04:18.895+08:00"},"s":"W",  "c":"CONTROL",  "id":22120,   "ctx":"initandlisten","msg":"Access control is not enabled for the database. Read and write access to data and configuration is unrestricted","tags":["startupWarnings"]}

{"t":{"$date":"2022-12-25T11:04:18.896+08:00"},"s":"W",  "c":"CONTROL",  "id":5123300, "ctx":"initandlisten","msg":"vm.max_map_count is too low","attr":{"currentValue":65530,"recommendedMinimum":102400,"maxConns":51200},"tags":["startupWarnings"]}

> show databases
admin   0.000GB
config  0.000GB
local   0.000GB
> help
	db.help()                    help on db methods
	db.mycoll.help()             help on collection methods
	sh.help()                    sharding helpers
	rs.help()                    replica set helpers
	help admin                   administrative help
	help connect                 connecting to a db help
	help keys                    key shortcuts
	help misc                    misc things to know
	help mr                      mapreduce

	show dbs                     show database names
	show collections             show collections in current database
	show users                   show users in current database
	show profile                 show most recent system.profile entries with time >= 1ms
	show logs                    show the accessible logger names
	show log [name]              prints out the last segment of log in memory, 'global' is default
	use <db_name>                set current database
	db.foo.find()                list objects in collection foo
	db.foo.find( { a : 1 } )     list objects in foo where a == 1
	it                           result of the last line evaluated; use to further iterate
	DBQuery.shellBatchSize = x   set default number of items to display on shell
	exit                         quit the mongo shell

[root@ubuntu2004 ~]#wget -qO - https://www.mongodb.org/static/pgp/server-6.0.asc | sudo apt-key add -
OK

[root@ubuntu2004 ~]#echo "deb [ arch=amd64,arm64 ] https://repo.mongodb.org/apt/ubuntu focal/mongodb-org/6.0 multiverse" | sudo tee /etc/apt/sources.list.d/mongodb-org-6.0.list
deb [ arch=amd64,arm64 ] https://repo.mongodb.org/apt/ubuntu focal/mongodb-org/6.0 multiverse

[root@ubuntu2004 ~]#apt update 

[root@ubuntu2004 ~]# apt-get install -y mongodb-mongosh

[root@ubuntu2004 ~]#mongosh
Current Mongosh Log ID:	63a7ed45c1f91515e0a766b3
Connecting to:		mongodb://127.0.0.1:27017/?directConnection=true&serverSelectionTimeoutMS=2000&appName=mongosh+1.6.1
Using MongoDB:		6.0.3
Using Mongosh:		1.6.1

For mongosh info see: https://docs.mongodb.com/mongodb-shell/


To help improve our products, anonymous usage data is collected and sent to MongoDB periodically (https://www.mongodb.com/legal/privacy-policy).
You can opt-out by running the disableTelemetry() command.

------
   The server generated these startup warnings when booting
   2022-12-25T11:04:18.124+08:00: Using the XFS filesystem is strongly recommended with the WiredTiger storage engine. See http://dochub.mongodb.org/core/prodnotes-filesystem
   2022-12-25T11:04:18.895+08:00: Access control is not enabled for the database. Read and write access to data and configuration is unrestricted
   2022-12-25T11:04:18.896+08:00: vm.max_map_count is too low
------

------
   Enable MongoDB's free cloud-based monitoring service, which will then receive and display
   metrics about your deployment (disk utilization, CPU, operation statistics, etc).
   
   The monitoring data will be available on a MongoDB website with a unique URL accessible to you
   and anyone you share the URL with. MongoDB may use this information to make product
   improvements and to suggest MongoDB products and deployment options to you.
   
   To enable free monitoring, run the following command: db.enableFreeMonitoring()
   To permanently disable this reminder, run the following command: db.disableFreeMonitoring()
------

Warning: Found ~/.mongorc.js, but not ~/.mongoshrc.js. ~/.mongorc.js will not be loaded.
  You may want to copy or rename ~/.mongorc.js to ~/.mongoshrc.js.
test> help

  Shell Help:

    use                                        Set current database
    show                                       'show databases'/'show dbs': Print a list of all available databases.
                                               'show collections'/'show tables': Print a list of all collections for current database.
                                               'show profile': Prints system.profile information.
                                               'show users': Print a list of all users for current database.
                                               'show roles': Print a list of all roles for current database.
                                               'show log <type>': log for current connection, if type is not set uses 'global'
                                               'show logs': Print all logs.

    exit                                       Quit the MongoDB shell with exit/exit()/.exit
    quit                                       Quit the MongoDB shell with quit/quit()
    Mongo                                      Create a new connection and return the Mongo object. Usage: new Mongo(URI, options [optional])
    connect                                    Create a new connection and return the Database object. Usage: connect(URI, username [optional], password [optional])
    it                                         result of the last line evaluated; use to further iterate
    version                                    Shell version
    load                                       Loads and runs a JavaScript file into the current shell environment
    enableTelemetry                            Enables collection of anonymous usage data to improve the mongosh CLI
    disableTelemetry                           Disables collection of anonymous usage data to improve the mongosh CLI
    passwordPrompt                             Prompts the user for a password
    sleep                                      Sleep for the specified number of milliseconds
    print                                      Prints the contents of an object to the output
    printjson                                  Alias for print()
    convertShardKeyToHashed                    Returns the hashed value for the input using the same hashing function as a hashed index.
    cls                                        Clears the screen like console.clear()
    isInteractive                              Returns whether the shell will enter or has entered interactive mode

  For more information on usage: https://docs.mongodb.com/manual/reference/method

[root@ubuntu2004 ~]#apt -y install python3-pip

[root@ubuntu2004 ~]#pip3 install pymongo
Collecting pymongo
  Downloading pymongo-4.3.3-cp38-cp38-manylinux2014_x86_64.whl (519 kB)
     |████████████████████████████████| 519 kB 1.3 MB/s 
Collecting dnspython<3.0.0,>=1.16.0
  Downloading dnspython-2.2.1-py3-none-any.whl (269 kB)
     |████████████████████████████████| 269 kB 8.7 MB/s 
Installing collected packages: dnspython, pymongo
Successfully installed dnspython-2.2.1 pymongo-4.3.3

[root@ubuntu2004 ~]#cat test_mongodb.py
#!/usr/bin/python3
from pymongo import MongoClient

# 客户端连接
#client = MongoClient(host='127.0.0.1', port=27017)
client = MongoClient('mongodb://127.0.0.1:27017')
print(client)

# 指定数据库 # Database类
#db = client.test
db = client['test']
print(db)

# 集合 Collection类
#users = db['users']
users = db.users
print(users)

for i in range(10):
  user = {'id':i, 'name':'test' + str(i), 'age':20}
  users.insert_one(user)
for x in users.find():
  print(x)
client.close()

client.close()
[root@ubuntu2004 ~]#python3 test_mongodb.py
MongoClient(host=['127.0.0.1:27017'], document_class=dict, tz_aware=False, connect=True)
Database(MongoClient(host=['127.0.0.1:27017'], document_class=dict, tz_aware=False, connect=True), 'test')
Collection(Database(MongoClient(host=['127.0.0.1:27017'], document_class=dict, tz_aware=False, connect=True), 'test'), 'users')
{'_id': ObjectId('63a7efc07d67261140a5fafe'), 'id': 0, 'name': 'test0', 'age': 20}
{'_id': ObjectId('63a7efc07d67261140a5faff'), 'id': 1, 'name': 'test1', 'age': 20}
{'_id': ObjectId('63a7efc07d67261140a5fb00'), 'id': 2, 'name': 'test2', 'age': 20}
{'_id': ObjectId('63a7efc07d67261140a5fb01'), 'id': 3, 'name': 'test3', 'age': 20}
{'_id': ObjectId('63a7efc07d67261140a5fb02'), 'id': 4, 'name': 'test4', 'age': 20}
{'_id': ObjectId('63a7efc07d67261140a5fb03'), 'id': 5, 'name': 'test5', 'age': 20}
{'_id': ObjectId('63a7efc07d67261140a5fb04'), 'id': 6, 'name': 'test6', 'age': 20}
{'_id': ObjectId('63a7efc07d67261140a5fb05'), 'id': 7, 'name': 'test7', 'age': 20}
{'_id': ObjectId('63a7efc07d67261140a5fb06'), 'id': 8, 'name': 'test8', 'age': 20}
{'_id': ObjectId('63a7efc07d67261140a5fb07'), 'id': 9, 'name': 'test9', 'age': 20}

[root@ubuntu2004 ~]#mongosh
Current Mongosh Log ID:	63a7eff68b3cc2ba95eae933
Connecting to:		mongodb://127.0.0.1:27017/?directConnection=true&serverSelectionTimeoutMS=2000&appName=mongosh+1.6.1
Using MongoDB:		6.0.3
Using Mongosh:		1.6.1

For mongosh info see: https://docs.mongodb.com/mongodb-shell/

------
   The server generated these startup warnings when booting
   2022-12-25T11:04:18.124+08:00: Using the XFS filesystem is strongly recommended with the WiredTiger storage engine. See http://dochub.mongodb.org/core/prodnotes-filesystem
   2022-12-25T11:04:18.895+08:00: Access control is not enabled for the database. Read and write access to data and configuration is unrestricted
   2022-12-25T11:04:18.896+08:00: vm.max_map_count is too low
------

------
   Enable MongoDB's free cloud-based monitoring service, which will then receive and display
   metrics about your deployment (disk utilization, CPU, operation statistics, etc).
   
   The monitoring data will be available on a MongoDB website with a unique URL accessible to you
   and anyone you share the URL with. MongoDB may use this information to make product
   improvements and to suggest MongoDB products and deployment options to you.
   
   To enable free monitoring, run the following command: db.enableFreeMonitoring()
   To permanently disable this reminder, run the following command: db.disableFreeMonitoring()
------

Warning: Found ~/.mongorc.js, but not ~/.mongoshrc.js. ~/.mongorc.js will not be loaded.
  You may want to copy or rename ~/.mongorc.js to ~/.mongoshrc.js.
test> db.users.find()
[
  {
    _id: ObjectId("63a7efc07d67261140a5fafe"),
    id: 0,
    name: 'test0',
    age: 20
  },
  {
    _id: ObjectId("63a7efc07d67261140a5faff"),
    id: 1,
    name: 'test1',
    age: 20
  },
  {
    _id: ObjectId("63a7efc07d67261140a5fb00"),
    id: 2,
    name: 'test2',
    age: 20
  },
  {
    _id: ObjectId("63a7efc07d67261140a5fb01"),
    id: 3,
    name: 'test3',
    age: 20
  },
  {
    _id: ObjectId("63a7efc07d67261140a5fb02"),
    id: 4,
    name: 'test4',
    age: 20
  },
  {
    _id: ObjectId("63a7efc07d67261140a5fb03"),
    id: 5,
    name: 'test5',
    age: 20
  },
  {
    _id: ObjectId("63a7efc07d67261140a5fb04"),
    id: 6,
    name: 'test6',
    age: 20
  },
  {
    _id: ObjectId("63a7efc07d67261140a5fb05"),
    id: 7,
    name: 'test7',
    age: 20
  },
  {
    _id: ObjectId("63a7efc07d67261140a5fb06"),
    id: 8,
    name: 'test8',
    age: 20
  },
  {
    _id: ObjectId("63a7efc07d67261140a5fb07"),
    id: 9,
    name: 'test9',
    age: 20
  }
]
test> 

show dbs|show databases #显示数据库,相当于MySQL中的show databases
use <库名> #切换数据库
use admin
> db #查看当前库相当于MySQL中的select database()
> db.shutdownServer() #关闭服务
show collections #显示表列表,相当于MySQL中的show tables
show tables

#use可以自动建库,如果库内没有数据,则不使用时会自动删除库
>use test
#删除当前所在库
>db.dropDatabase()
{ "dropped" : "test", "ok" : 1 }
#可以直接切换至不存在的库
>use testdb1
>db
testdb1

#建表方法1:直接创建表
app>db.createCollection ('student')

#建表方法2:当插入一个文档的时候，一个集合就会自动创建。
use magedu
db.test.insert ({name: " wang"})
db.student.insert({id:1, name : "wang" ,age:20, gender: "m" })
db.student.insert ({id:2, name: "zhao"})
db.student.insert([{id:3,name: "tom",age: 22},{id:4,name: "jerry",age: 23}])
db.student.insert ({a: "b",c: "d"})
db.student.insert ({a:1,c:2})

#查看库中的集合列表
show tables
show collections

#查看集合的信息
db.student.stats()

#删除集合
db.student.drop()

#数据录入:
for(i=0;i<10000;i++){db.student.insert({uid:i, name: "wang"+i , "age":18,"date": new Date()})}
for(i=0;i<10000;i++){db.users.insert({uid:i, name: "wang"+i ,"age":i,address:"beijing"})}
for(i=0;i<10000;i++){db.random.insertOne({num: Math.random()* 100000})}

#查询数据行数:
db.student.count()

#全表查询,默认每页显示20行
db.student.find()
it #继续显示下面行

#只显示前3个
db.student.find().limit(3)

#跳过前面10个显示后面的文档
db.student.find().skip(10)

#每页显示50条记录:
DBQuery.shellBatchsize=50

#按照条件查询
db.student.find({uid: 10})

#查询大于等于18并正序排序users集合
db.users.find({age: { $gte: 18 }}).sort({age: 1})

#查询users集合中的小于18的前5个文档中两个key:name和address
db.users.find({age: {$lt: 18 }},{ name: 1, address: 1}).limit(5)

#以标准的json格式显示数据
db.student.find({uid:10}).pretty()

#显示效果如下
{
"id": objectId ( "8bc516e60d13144c89dead66"),
"uid": 10,
"name": "wang10",
"age": 18,
"date": ISODate ( "2018-01-12T02:38:57.113Z")
}

#修改文档,如果没有加multi: true.默认只修改第一个符合条件的文档
db.student.update({uid:1},{$set:{age: 20}},{multi: true})

#删除指定的文档
db.student.remove({uid: 10})

#删除集合中所有记录,但表还存在
db.student.remove({})

#查看集合存储信息,包括集合中索引和数据压缩存储后的大小
db.student.totalSize()

#注意:启用认证后,仍然可以直接登录,但无权限做数据操作,但可以创建用户
#方法1:命令行方式通过“--auth”参数
mongod --auth --port 27017 --dbpath /data/db

#方法2,修改配置文件中，加入以下配置
cat >> /mongodb/conf/mongo.conf <<EOF
security:
authorization: enabled
EOF
systemctl restart mongod

#创建用户
use <db> #切换至需要创建用户的验证库后,再创建用户
db.createUser (
  {
   user: "<name>",
   pwd: "<cleartext password>",
   roles:[
     { role: "<role>",
     db : "<database>"}|"<role>",
     .....
     }]
  }
)

#基本语法说明:
user:用户名
pwd:密码
roles:
  role:角色名,比如:root, readWrite, read
  db:上面角色作用的数据库对象

#验证用户
use <验证库>
db.auth('用户名', '密码')

#用户保存在admin库的users集合中
use admin
db.system.users.find()

#登录验证
mongo -u用户名 -p密码 <验证库> #本地登录,如果验证库admin省略,登录后默认在test库
mongo -u用户名 -p密码 <MongoDB主机IP>/<验证库> #远程登录,验证库不可以省略

#修改密码
db.changeUserPassword("用启名", "新密码")

#删除用户
use <验证库>
db.dropUser("用户名")

#创建超级管理员root(也可以是任意用户名)管理所有数据库（必须use admin再去创建,因为超级用户是存放在admin库中的）
test> use admin
switched to db admin
admin> db.createUser ( {user: "root",pwd: "123456",roles: [{role: "root", db: "admin"}]})
{ ok: 1 }

[root@ubuntu2004 ~]#cat /mongodb/conf/mongo.conf 
systemLog:
  destination: file
  path: "/mongodb/log/mongodb.log"
  logAppend: true

storage:
  dbPath: "/mongodb/data/"
  journal:
    enabled: true
 
processManagement:
  fork: true

net:
  port: 27017
  bindIp: 0.0.0.0


security:
  authorization: enabled


[root@ubuntu2004 ~]#mongo -uroot -p123456 admin
MongoDB shell version v3.6.8
connecting to: mongodb://127.0.0.1:27017/admin
Implicit session: session { "id" : UUID("a781277d-38d9-479f-8a40-e3776f6e6531") }
MongoDB server version: 6.0.3
WARNING: shell and server versions do not match
Server has startup warnings: 
{"t":{"$date":"2022-12-25T15:02:52.189+08:00"},"s":"I",  "c":"STORAGE",  "id":22297,   "ctx":"initandlisten","msg":"Using the XFS filesystem is strongly recommended with the WiredTiger storage engine. See http://dochub.mongodb.org/core/prodnotes-filesystem","tags":["startupWarnings"]}

{"t":{"$date":"2022-12-25T15:02:52.831+08:00"},"s":"W",  "c":"CONTROL",  "id":5123300, "ctx":"initandlisten","msg":"vm.max_map_count is too low","attr":{"currentValue":65530,"recommendedMinimum":102400,"maxConns":51200},"tags":["startupWarnings"]}

> show databases
admin   0.000GB
config  0.000GB
local   0.000GB
test    0.000GB
> db
admin
> db.system.users.find().pretty()
{
	"_id" : "admin.root",
	"userId" : UUID("f39ee7be-3710-4ff3-9bec-44d26604c7ed"),
	"user" : "root",
	"db" : "admin",
	"credentials" : {
		"SCRAM-SHA-1" : {
			"iterationCount" : 10000,
			"salt" : "VlkxPPGp1hMqF2p9+WZyzA==",
			"storedKey" : "bTCX2BOK2UtHPbNUppMlOnUkXyo=",
			"serverKey" : "IJUu13kdY0408wGSWv1F023ZuGQ="
		},
		"SCRAM-SHA-256" : {
			"iterationCount" : 15000,
			"salt" : "M1Bax395i7gyrlQU7J93DcP6e0NBHP4NGdybzw==",
			"storedKey" : "cJaKpXJGucE0lrB9HJfeLNEtVJgM2sJ+7qRvo8+syYg=",
			"serverKey" : "19jcJGX/77FU6mXsxCZiU0fTOK+xZnXoun7MKWHeffQ="
		}
	},
	"roles" : [
		{
			"role" : "root",
			"db" : "admin"
		}
	]
}
> db.getUsers()
[
	{
		"_id" : "admin.root",
		"userId" : UUID("f39ee7be-3710-4ff3-9bec-44d26604c7ed"),
		"user" : "root",
		"db" : "admin",
		"roles" : [
			{
				"role" : "root",
				"db" : "admin"
			}
		],
		"mechanisms" : [
			"SCRAM-SHA-1",
			"SCRAM-SHA-256"
		]
	}
]

[root@ubuntu2004 ~]#mongosh -u root -p 123456 admin
Current Mongosh Log ID:	63a7fbf0a20f88a08f73596c
Connecting to:		mongodb://<credentials>@127.0.0.1:27017/admin?directConnection=true&serverSelectionTimeoutMS=2000&appName=mongosh+1.6.1
Using MongoDB:		6.0.3
Using Mongosh:		1.6.1

For mongosh info see: https://docs.mongodb.com/mongodb-shell/

------
   The server generated these startup warnings when booting
   2022-12-25T15:02:52.189+08:00: Using the XFS filesystem is strongly recommended with the WiredTiger storage engine. See http://dochub.mongodb.org/core/prodnotes-filesystem
   2022-12-25T15:02:52.831+08:00: vm.max_map_count is too low
------

------
   Enable MongoDB's free cloud-based monitoring service, which will then receive and display
   metrics about your deployment (disk utilization, CPU, operation statistics, etc).
   
   The monitoring data will be available on a MongoDB website with a unique URL accessible to you
   and anyone you share the URL with. MongoDB may use this information to make product
   improvements and to suggest MongoDB products and deployment options to you.
   
   To enable free monitoring, run the following command: db.enableFreeMonitoring()
   To permanently disable this reminder, run the following command: db.disableFreeMonitoring()
------

Warning: Found ~/.mongorc.js, but not ~/.mongoshrc.js. ~/.mongorc.js will not be loaded.
  You may want to copy or rename ~/.mongorc.js to ~/.mongoshrc.js.
admin> use test
switched to db test
test> db.createUser({user:"testet",pwd:"123456",roles: [ { role: "readWrite", db: "test" },{ role: "read", db: "reporting" } ] })
{ ok: 1 }
test> 


[root@ubuntu2004 ~]#mongosh -u testet -p 123456 test
Current Mongosh Log ID:	63a7fc1d55b83d5fcea758a7
Connecting to:		mongodb://<credentials>@127.0.0.1:27017/test?directConnection=true&serverSelectionTimeoutMS=2000&appName=mongosh+1.6.1
Using MongoDB:		6.0.3
Using Mongosh:		1.6.1

For mongosh info see: https://docs.mongodb.com/mongodb-shell/

Warning: Found ~/.mongorc.js, but not ~/.mongoshrc.js. ~/.mongorc.js will not be loaded.
  You may want to copy or rename ~/.mongorc.js to ~/.mongoshrc.js.
test> 

#以管理员root身份登录，use到被删除用户的验证库才能删除用户
[root@ubuntu2004 ~]#mongosh -u root -p 123456 admin
Current Mongosh Log ID:	63a7fc746b98487c2a3c542f
Connecting to:		mongodb://<credentials>@127.0.0.1:27017/admin?directConnection=true&serverSelectionTimeoutMS=2000&appName=mongosh+1.6.1
Using MongoDB:		6.0.3
Using Mongosh:		1.6.1

For mongosh info see: https://docs.mongodb.com/mongodb-shell/

------
   The server generated these startup warnings when booting
   2022-12-25T15:02:52.189+08:00: Using the XFS filesystem is strongly recommended with the WiredTiger storage engine. See http://dochub.mongodb.org/core/prodnotes-filesystem
   2022-12-25T15:02:52.831+08:00: vm.max_map_count is too low
------

------
   Enable MongoDB's free cloud-based monitoring service, which will then receive and display
   metrics about your deployment (disk utilization, CPU, operation statistics, etc).
   
   The monitoring data will be available on a MongoDB website with a unique URL accessible to you
   and anyone you share the URL with. MongoDB may use this information to make product
   improvements and to suggest MongoDB products and deployment options to you.
   
   To enable free monitoring, run the following command: db.enableFreeMonitoring()
   To permanently disable this reminder, run the following command: db.disableFreeMonitoring()
------

Warning: Found ~/.mongorc.js, but not ~/.mongoshrc.js. ~/.mongorc.js will not be loaded.
  You may want to copy or rename ~/.mongorc.js to ~/.mongoshrc.js.
admin> use test
switched to db test
test> db.dropUser ("testet")
{ ok: 1 }
test> db.system.users.find().pretty()

[root@ubuntu2004 ~]#cat /mongodb/conf/mongo.conf 
systemLog:
  destination: file
  path: "/mongodb/log/mongodb.log"
  logAppend: true

storage:
  dbPath: "/mongodb/data/"
  journal:
    enabled: true
 
processManagement:
  fork: true

net:
  port: 27017
  bindIp: 0.0.0.0

replication:
  replSetName: myrepl  #指定复制集名称,所有复制集成员此名称要一致

#其余两台同上

方法一:
#登录mongodb输入以下配置信息实现主从配置
config = { _id: 'myrepl', members: [
     {_id: 0, host: '10.0.0.208:27017'},
     {_id: 1, host: '10.0.0.209:27017'} ,
     {_id: 2, host: '10.0.0.210:27017'}]
     }

rs.initiate(config)

[root@ubuntu2004 ~]#mongosh 
...
test> config = { _id: 'myrepl', members: [
... {_id: 0, host: '10.0.0.208:27017'},
... {_id: 1, host: '10.0.0.209:27017'} ,
... {_id: 2, host: '10.0.0.210:27017'}]
... }
{
  _id: 'myrepl',
  members: [
    { _id: 0, host: '10.0.0.208:27017' },
    { _id: 1, host: '10.0.0.209:27017' },
    { _id: 2, host: '10.0.0.210:27017' }
  ]
}
test> printjson(config)
{
  _id: 'myrepl',
  members: [
    {
      _id: 0,
      host: '10.0.0.208:27017'
    },
    {
      _id: 1,
      host: '10.0.0.209:27017'
    },
    {
      _id: 2,
      host: '10.0.0.210:27017'
    }
  ]
}

test> rs.initiate(config)
{ ok: 1 }
myrepl [direct: other] test> db.printReplicationInfo()
actual oplog size
'4396.328125 MB'
---
configured oplog size
'4396.328125 MB'
---
log length start to end
'12 secs (0 hrs)'
---
oplog first event time
'Mon Dec 26 2022 10:42:09 GMT+0800 (中国标准时间)'
---
oplog last event time
'Mon Dec 26 2022 10:42:21 GMT+0800 (中国标准时间)'
---
now
'Mon Dec 26 2022 10:42:37 GMT+0800 (中国标准时间)'
myrepl [direct: primary] test> rs.
rs.__proto__                      rs.constructor                    rs.hasOwnProperty                 rs.isPrototypeOf                  rs.propertyIsEnumerable           rs.toLocaleString                 rs.toString
rs.valueOf                        rs.initiate                       rs.config                         rs.conf                           rs.reconfig                       rs.reconfigForPSASet              rs.status
rs.isMaster                       rs.hello                          rs.printSecondaryReplicationInfo  rs.printReplicationInfo           rs.add                            rs.addArb                         rs.remove
rs.freeze                         rs.stepDown                       rs.syncFrom

myrepl [direct: primary] test> rs.isMaster
[Function: isMaster] AsyncFunction {
  apiVersions: [ 0, 0 ],
  returnsPromise: true,
  serverVersions: [ '0.0.0', '999.999.999' ],
  topologies: [ 'ReplSet', 'Sharded', 'LoadBalanced', 'Standalone' ],
  returnType: { type: 'unknown', attributes: {} },
  deprecated: false,
  platforms: [ 'Compass', 'Browser', 'CLI' ],
  isDirectShellCommand: false,
  acceptsRawInput: false,
  shellCommandCompleter: undefined,
  help: [Function (anonymous)] Help
}
myrepl [direct: primary] test> 



方法二:
rs.initiate ( )
rs.add("10.0.0.209:27017")
rs.add("10.0.0.210:27017")

#查询复制集状态
rs.status()
rs.hello()
rs.isMaster()

#显示复制信息
db.printReplicationInfo()

config = { _id: 'myrepl', members: [
{ _id: 0, host: '10.0.0.208:28017'},
{ _id: 1, host: '10.0.0.209:27017'},
{ _id: 2, host: '10.0.0.210:27017', "arbiterOnly": true}]
}

rs.initiate (config)

#查询复制集状态
rs.status()

myrepl:PRIMARY> rs.remove ("10.0.0.100:28019")
myrepl:PRIMARY> rs.addArb ("10.0.0.100:28019")

#查看整体复制集状态
rs.status()
#查看当前是否是主节点
rs.isMaster()
#查看复制集配置信息
rs.conf()

#删除一个节点
rs.remove ("ip: port")
#新增从节点
rs.add ("ip: port")
#新增仲裁节点
rs.addArb ("ip: port")

#添加一个节点
myrepl:PRIMARY> rs.add ("10.0.0.208:27017")
#删除一个节点
myrepl:PRIMARY> rs.remove ("10.0.0.209:27017")
{ "ok” : 1 }
myrepl:PRIMARY>rs.isMaster()

#在主节点执行下面操作配置特殊节点并保存
config=rs.conf() #定义变量
config.members[3].hidden=true #设置hidden,3表示第4个成员,从0开始表示第1个,是
rs.conf()显示的顺序,不是_id的值
config.members[3].priority=0 #优先级0表示不参选master，但可以投票,值越大优先级越高
config.members[3].arbiterOnly=true #也可将延时节点配置为arbiter节点
config.members[3].slaveDelay=120 #延时时长,以秒为单位,生产可延时3-6小时
config.members[3].votes=0 #持有票数为0
rs.reconfig(config) #加载配置

#取消以上配置
config=rs.conf()
config.members[3].priority=1
config.members[3].hidden=false
config.members[3].slaveDelay=0
config.members[3].votes=1
rs.reconfig(config)

#配置成功后,通过以下命令查询配置后的属性
rs.conf();

#打开从节点读支持
#新版命令
myrepl:SECONDARY> rs.secondaryOk()
#旧版命令已废弃
myrepl:SECONDARY> rs.slaveOk()

A=所需存储总量/单服务器可挂载容量
如:8TB/2TB = 4
B=工作集大小/(单服务器物理内存容量*0.6) #0.6表示mongodb默认使用内存的60%
如:400GB / (256G*0.6) = 3
C=并发量总数/（单服务器并发量*0.7) #0.7表示单机变成分片有额外开销
如:30000/(9000*0.7)= 6

#结果:
分片数量=max(A,B,C)=6

准备十台主机,角色分配如下
shard1
10.0.0.8:27017
10.0.0.18:27017
10.0.0.28:27017
shard2
10.0.0.38:27017
10.0.0.48:27017
10.0.0.58:27017
config server
10.0.0.68:27019
10.0.0.78:27019
10.0.0.88:27019
mongos
10.0.0.98:27017

#在shard1的三个节点上执行下面操作
[root@rocky8 ~]#cat > /mongodb/conf/mongo.conf <<EOF
systemLog:
  destination: file
  path: "/mongodb/log/mongodb.log"
  logAppend: true
storage:
  dbPath: "/mongodb/data/"
  journal:
    enabled: true
processManagement:
  fork: true
net:
  port: 27017
  bindIp: 0.0.0.0
replication :
  oplogSizeMB: 2048
  replSetName: shard1
sharding:
  clusterRole: shardsvr
EOF

[root@rocky8 ~]#systemctl restart mongod.service
#在10.0.0.8节点执行下面操作
[root@rocky8 ~]#mongo
use admin
config = { _id: 'shard1', members: [
            {_id: 0, host: '10.0.0.8:27017'},
            {_id: 1, host: '10.0.0.18:27017'},
            {_id: 2, host: '10.0.0.28:27017'}]
}

rs.initiate (config)

#在shard2的三个节点上执行下面操作
[root@rocky8 ~]#cat > /mongodb/conf/mongo.conf <<EOF
systemLog:
  destination: file
  path: "/mongodb/log/mongodb.log"
  logAppend: true
storage:
  dbPath: "/mongodb/data/"
  journal:
    enabled: true
processManagement:
  fork: true
net:
  port: 27017
  bindIp: 0.0.0.0
replication :
  oplogSizeMB: 2048
  replSetName: shard2
sharding:
  clusterRole: shardsvr
EOF

[root@rocky8 ~]#systemctl restart mongod.service
#在10.0.0.38节点执行下面操作
[root@rocky8 ~]#mongo
use admin
config = { _id: 'shard2', members: [
            {_id: 0, host: '10.0.0.38:27017'},
            {_id: 1, host: '10.0.0.48:27017'},
            {_id: 2, host: '10.0.0.58:27017'}]
}

rs.initiate (config)

#在config的三个节点上执行下面操作
[root@rocky8 ~]#cat > /mongodb/conf/mongo.conf <<EOF
systemLog:
  destination: file
  path: "/mongodb/log/mongodb.log"
  logAppend: true
storage:
  dbPath: "/mongodb/data/"
  journal:
    enabled: true
processManagement:
  fork: true
net:
  bindIp: 0.0.0.0
replication:
  oplogSizeMB: 2048
  replSetName: config
sharding:
  clusterRole: configsvr
EOF

[root@rocky8 ~]#systemctl restart mongod.service
#在10.0.0.68节点执行下面操作,注意:config server的端口默认是27019
[root@rocky8 ~]#mongo --port 27019
use admin
config = { _id: 'config', members: [
            {_id: 0, host: '10.0.0.68:27019' },
            {_id: 1, host: '10.0.0.78:27019'} ,
            {_id: 2, host: '10.0.0.88:27019'}]
}

rs.initiate (config)

#配置mongs节点
#在mongos节点10.0.0.98节点执行下面操作
[root@rocky8 ~]#cat > /mongodb/conf/mongo.conf <<EOF
systemLog:
  destination: file
  path: "/mongodb/log/mongodb.log"
sharding:
  configDB: config/10.0.0.68:27019,10.0.0.78:27019,10.0.0.88:27019
net:
  bindIp: 0.0.0.0
processManagement:
  fork: true
EOF

#先停止原mongod服务
[root@rocky8 ~]#systemctl stop mongod

#启动mongs,注意不是mongod
[root@rocky8 ~]#mongos -f /mongodb/conf/mongo.conf
[root@rocky8 ~]#ss -ntlp|grep mongos
LISTEN 0 128 0.0.0.0:27017 0.0.0.0:* users: (("mongos",pid=1928,fd=13))

#添加分片
[root@rocky8 ~]#mongo admin
mongos>sh.addShard("shard1/10.0.0.8:27017")
mongos>sh.addShard("shard2/10.0.0.38:27017")
#或者
mongos>sh.addShard("shard1/10.0.0.8:27017,10.0.0.18:27017,10.0.0.28:27017")
mongos>sh.addShard("shard2/10.0.0.38:27017,10.0.0.48:27017,10.0.0.58:27017")

#查看分片状态
mongos> sh.status()
--- Sharding Status ---
sharding version: {
  "_id" : 1,
  "minCompatibleVersion" : 5,
  "currentVersion" : 6,
  "clusterId" : ObjectId("619510ec03c01fb9bc4a22aa")
}
shards:
  { "_id" : "shard1", "host" : "shard1/10.0.0.18:27017,10.0.0.8:27017","state" : 1, "topologyTime" : Timestamp(1637160656, 5) }
  { "_id" : "shard2", "host" : "shard2/10.0.0.38:27017,10.0.0.48:27017","state" : 1, "topologyTime" : Timestamp(1637160679, 5) }
active mongoses:
  "5.0.3" : 1
autosplit:
  Currently enabled: yes
balancer:
  Currently enabled: yes
  Currently running: no
  Failed balancer rounds in last 5 attempts: 0
  Migration results for the last 24 hours:
  No recent migrations
databases:
  { "_id" : "config", "primary" : "config", "partitioned" : true }

mongos> db.runCommand({listshards: 1})
{
  "shards" : [
  {
     "_id" : "shard1",
     "host" : "shard1/10.0.0.18:27017,10.0.0.8:27017",
     "state" : 1,
     "topologyTime" : Timestamp(1637160656, 5)
  },
  {
     "_id" : "shard2",
     "host" : "shard2/10.0.0.38:27017,10.0.0.48:27017",
     "state" : 1,
     "topologyTime" : Timestamp(1637160679, 5)
  }
],
"ok" : 1,
"$clusterTime" : {
  "clusterTime" : Timestamp(1637160731, 1),
  "signature" : {
     "hash" : BinData(0,"AAAAAAAAAAAAAAAAAAAAAAAAAAA="),
     "keyId" : NumberLong(0)
  }
},
"operationTime" : Timestamp(1637160731, 1)
}

#启用数据库的分片
mongos> sh.enableSharding("test")

#创建索引
mongos>use test
mongos>db.vast.createIndex({id: 1}) #针对id字段从小到大创建索引

#开启range分片规则
mongos>sh.shardCollection("test.vast", {id: 1})
#或者
mongos>db.runCommand({shardcollection: "test.vast",key: {id: 1}})

#如果是对_id进行range分片,无需创建索引
mongos>sh.shardCollection("test.vast", {_id: 1})
#或者
mongos>db.runCommand({shardcollection: "test.vast",key: {_id: 1}})

#插入足够的大量数据才会分片
mongos> use test
mongos> for (i=0;i<1000000 ;i++){ db.vast.insert ( { "id" :i, "name" : "shu" ,"age" : 20,"date" : new Date()})}

#启用数据库的分片
mongos> sh.enableSharding("magedu")
#指定在magedu库的vast表的id列上创建hash索引
mongos> use magedu
mongos> db.vast.createIndex({id: "hashed"} )

#指定表分片基于hash规则
mongos> sh.shardCollection("magedu.vast", {id: 'hashed'})
#或者
mongos>db.runCommand({shardcollection: "magedu.vast",key: {id: 'hashed'}})

#插入足够的大量数据才会分片
mongos> use magedu
mongos> for (i=0;i<1000000 ;i++){ db.vast.insert ( { "id" :i, "name" : "shu" ,"age" : 20,"date" : new Date()})}

#查看分片
mongos> db.adminCommand({listShards: 1})
mongos> db.runCommand({listshards: 1})

#查看分片
mongos> db.adminCommand({listShards: 1})
mongos> db.runCommand ({listshards: 1})
mongos> sh.status()
mongos> use config
mongos> db.databases.find()
#分别在shard1和shard2上验证数据数量
use test
db.vast.count()
use magedu
db.vast.count()

mongos> sh.stopBalancer()
mongos> sh.startBalancer()

#自定义自动平衡进行的时间段
https://docs.mongodb.com/manual/tutorial/manage-sharded-cluster-balancer/#schedule-the-balancing-window

#connect to mongos
mongo --port 38017 admin
use config
sh.setBalancerState(true)
sh.getBalancerState()

#设置3:00到5:00进行balance
db.settings.update({id: "balancer"},{$set: {activeWindow:{start: "3:00",stop :"5:00"}}}, true)

sh.getBalancerWindow()
sh.status()

db.settings.find()
{ "_id" : "chunksize", "value" : 4 }
{ "_id" : ObjectId("619a0c8d251b017dc44bfde2"), "id" : "balancer",
"activeWindow" : { "start" : "3:00", "stop" : "5:00" } }
{ "_id" : "balancer", "mode" : "full", "stopped" : false }
{ "_id" : "autosplit", "enabled" : true }

#关闭某个集合的balancer
sh.disableBalancing("test.vast")

#打开某个集合的balancer
sh.enableBalancing ("test.vast")

#确定某个集合的balance是开启或者关闭
db.getSiblingDB("config").collections.findOne({_id : "magedu.vast"}).noBalance

https://docs.mongodb.com/database-tools/mongoexport/#mongodb-binary-bin.mongoexport
Versioning
Starting with MongoDB 4.4, mongoexport is now released separately from the
MongoDB Server and uses its own versioning, with an initial version of 100.0.0.
Previously, mongoexport was released alongside the MongoDB Server and used
matching versioning.
For documentation on the MongoDB 4.2 or earlier versions of mongoexport,
reference the MongoDB Server Documentation for that version of the tool:

下载链接:
https://www.mongodb.com/try/download/database-tools

$mongoexport --help
参数说明:
-h #指明数据库宿主机的IP
-u #指明数据库的用户名
-p #指明数据库的密码
-d #指明数据库的名字
-c #指明collection的名字
-f #指明要导出那些列
-o #指明到要导出的文件名
-q #指明导出数据的过滤条件
--type=csv或 --csv #指定导出为csv格式，默认json格式
--authenticationDatabase <验证库> #指定验证库

#单表备份至json格式
mongoexport -uroot -p123456 --port 27017 --authenticationDatabase admin -d test -c vast -o /mongodb/vast.json
mongoexport -d test -c log -f uid,name -q='{"uid":3}' -o vast.json
#单表备份至csv格式，则需要使用--type=csv参数
mongoexport -uroot -p123456 --port 27017 --authenticationDatabase admin -d test -c vast --type=csv -f uid,name,age,date -o /mongodb/vast.csv

mongoimport --help
#参数说明:
-h #指明数据库宿主机的IP
-u #指明数据库的用户名
-p #指明数据库的密码
-d #指明数据库的名字
-c #指明collection的名字
-f #指明要导入那些列
--type=csv #指定导入csv格式文件，默认json格式
-j，--numInsertionworkers=<number> #同时插入的数量,默认为
--headerline #指明第一行是列名，不需要导

#导入json格式表数据到vast1表中
mongoimport -uroot -p123456 --port 27017 --authenticationDatabase admin -d test -c vast1 /mongodb/vast.json
#导入标准的csv格式(文件第一行有列名字)的文件到vast2表中
mongoimport-uroot -p123456 --port 27017 --authenticationDatabase admin -d test -c vast2 --type=csv --headerline --file /mongodb/vast.csv
#导入非标准的csv格式(第一行没有列名字)的文件到vast3表中
mongoimport -uroot -p123456 --port 27017 --authenticationDatabase admin -d test -c vast3 --type=csv -f id,name, age,date --file/mongodb/vast.csv

#将hellodb数据库下students表进行导出，导入到mongodb
1) mysql开启安全路径
vim /etc/my.cnf
[mysqld]
secure-file-priv=/tmp

vim /lib/systemd/system/mysqld.service
#PrivateTmp=true 将此行注释,否则会在/tmp/生成如下类似的临时的子目录
/tmp/systemd-private-4e55a87321e741b7b98959db343effa5-mysqld.service-JsMtwj/tmp/students_info.csv

#重启数据库生效
systemctl restart mysqld

2）导出mysql的students表数据
#默认导出为Tab分隔的csv文件
mysql> select * from hellodb.students into outfile '/tmp/students.csv';
#指定导出分隔符为,的csv文件
mysql> select * from hellodb.students into outfile '/tmp/students.csv' fieldsterminated by ',';

3)导出列名
#如果列很多,可以使用infomation_schema.columns导出列名
select column_name from information_schema.columns where table_schema='hellodb' and table_name='students';
#group_concat函数可以多行合并成一行显示
select group_concat(column_name) from information_schema.columns where table_schema='hellodb' and table_name='students';

4)在mongodb中导入备份
#方法1
将第3步查出的列名加入到前面导出的文件students.csv的第一行
mongoimport -uroot -p123456 --port 27017 --authenticationDatabase admin -d test -c students --type=csv --headerline --file /tmp/students.csv
#方法2:使用选项 -f 指定列名
mongoimport -uroot -p123456 --port 27017 --authenticationDatabase admin -d test -c students --type=csv -f StuID,Name,Age,Gender,ClassID,TeacherID --file /tmp/students.csv

1) mysql开启安全路径
vim /etc/my.cnf
[mysqld]
secure-file-priv=/data/mysql

vim /lib/systemd/system/mysqld.service
#PrivateTmp=true 将此行注释,否则会在/tmp/生成临时的子目录

#重启数据库生效
systemctl restart mysqld

mkdir -p /data/mysql
chown mysql.mysql /data/mysql

2)导出students表到目录中，生成以Tab分割的文本文件
mysqldump hellodb students -T /data/mysql

ls /data/mysql/
students.sql students.txt

3)将tab替换为,
sed -i.bak 's/\t/,/g' /data/mysql/students.txt

4)导入mongodb
mongoimport -d test -c students -f stuid,name,age,gender,classid,teacherid --type=csv /data/mysql/students.txt

[root@rocky8 ~]#head /tmp/students_info.csv
1,Shi Zhongyu,22,M,2,3
2,Shi Potian,22,M,1,7
3,Xie Yanke,53,M,2,16
4,Ding Dian,32,M,4,4
5,Yu Yutong,26,M,3,1
6,Shi Qing,46,M,5,\N
7,Xi Ren,19,F,3,\N
8,Lin Daiyu,17,F,7,\N
9,Ren Yingying,20,F,6,\N
10,Yue Lingshan,19,F,3,\N
mysql> use hellodb
Database changed
mysql> create table students_info like students;
mysql> load data infile '/tmp/students_info.csv' into table students_info fields terminated by ',' optionally enclosed by '"';

mongodump --help
参数说明:
-h #指明数据库宿主机的IP
-u #指明数据库的用户名
-p #指明数据库的密码
-d #指明数据库的名字
-c #指明collection的名字
-o #指明到要导出的文件名
-q #指明导出数据的过滤条件
-j, --numParallelCollections= #并行导出的数量,默认为4
--oplog #备份的同时备份oplog,此选项是replica set或者master/ slave模式专用

mongorestore --help
-h #指明数据库宿主机的IP
-u #指明数据库的用户名
-p #指明数据库的密码
-d #指明数据库的名字
-c #指明collection的名字
-o #指明到要导出的文件名
-q #指明导出数据的过滤条件
--authenticationDatabase #验证数据的名称
--gzip #备份时压缩
--oplogReplay #恢复完数据文件后再重放oplog。默认重放dump/oplog.bson
--oplogFile=<filename> #指定需要重放的oplog文件位置
--oplogLimit=<seconds>[:ordinal] #重放oplog 时截止到指定时间点
--drop #恢复的时候把之前的集合drop掉

#全库备份
#注意:完全备份不会备份config和local库,但会备份admin库和test库及用户库
mkdir -p /backup/full
mongodump -uroot -p123456 --port 27017 --authenticationDatabase admin -o /backup/full
mongodump -uroot -p123456 --port 27017 --authenticationDatabase admin -o /backup/full-date +%F

#备份指定库test
mkdir -p /backup/test_backup
mongodump -uroot -p123456 --port 27017 --authenticationDatabase admin -d test -o /backup/test_backup

#备份magedu库下的vast集合
mkdir -p /backup/vast
mongodump-uroot -p123456 --port 27017 --authenticationDatabase admin -d magedu -c vast -o /backup/vast

#完全备份并压缩备份
mkdir -p /backup/full_gzip
mongodump -uroot -p123456 --port 27017 --authenticationDatabase admin -o /backup/full_gzip --gzip

恢复完全备份
mongorestore -uroot -p123456 --port 27017 --authenticationDatabase admin /backup/full

#从完全备份的压缩备份中的test库恢复至test1库
mongorestore -uroot -p123456 --port 27017 --authenticationDatabase admin -d test1 /backup/full_gzip/test --gzip

#从完全备份中的vast表恢复到test库中的test库的表vast1中
mongorestore-uroot -p123456 --port 27017 --authenticationDatabase admin -d test -c vast1 --gzip /backup/full_gzip/test/vast.bson.gz

#默认不允许覆盖恢复会报错,可以使用选项--drop实现覆盖恢复,表示恢复的时候先之前的集合drop掉(危险),再恢复
mongorestore -uroot -p123456 --port 27017 --authenticationDatabase admin -d magedu --drop /backup/magedu

#关于oplog说明: 官方:https://docs.mongodb.com/manual/core/replica-set-oplog/
类似于MySQL中的binlog,记录了MongoDB数据的更新,只支持复制集,不支持单节点
在replica set中oplog是一个定容集合(capped collection,固定大小)，保存在local库的
db.oplog.rs
它的默认大小是磁盘空间的5%（可以通过--oplogSizeMB参数修改).
其中记录的是整个mongod实例一段时间内数据库的所有变更(插入/更新/删除）操作。
当空间用完时新记录自动覆盖最老的记录。
其覆盖范围被称作oplog时间窗口。
需要注意的是，因为oplog是一个定容集合，所以时间窗口能覆盖的范围会因为单位时间内的更新次数不同而
变化。
至少要预留MongoDB的1个全备的周期大小。
默认情况下，MongoDB 不设置最小 oplog 保留期，并自动从最旧的条目开始截断 oplog，以保持配置的最
大 oplog 大小
oplog有一个非常重要的特性——幂等性（idempotent）。即对一个数据集合，使用oplog中记录的操作重放
时，无论被重放多少次，其结果会是一样的。比如，如果oplog中记录的是一个插入操作，并不会因为你重放
了两次，数据库中就得到两条相同的记录。这是一个很重要的特性.

#注意：此操作不要在分片集群中执行
#单机默认没有oplog，需要实现复制集才能开启oplog
[root@ubuntu1804 ~]#cat /mongodb/conf/mongo.conf
systemLog:
  destination: file
  path: "/mongodb/log/mongodb.log"
  logAppend: true
storage:
  dbPath: "/mongodb/data/"
  journal:
    enabled: true
processManagement:
  fork: true
net:
  port: 27017
bindIp: 0.0.0.0
replication:
  replSetName: myrepl

[root@ubuntu1804 ~]#systemctl restart mongod

#开启复制集
[root@ubuntu1804 ~]#mongo
>rs.initiate()
>rs.initiate({ _id: "myrepl", members: [{_id:0,host:"10.0.0.8:27017"}]})

#查看复制集和oplog信息
myrepl:PRIMARY> rs.printReplicationInfo()
configured oplog size: 4622.462158203125MB #集合大小
log length start to end: 245022secs (68.06hrs) #oplog 存在时长
oplog first event time: Wed Nov 20 2019 17:52:05 GMT+0800 (CST)
oplog last event time: Wed Nov 20 2019 17:52:05 GMT+0800 (CST)
now: Wed Nov 20 2019 17:52:15 GMT+0800 (CST)

#插入大量数据，同时执行后面的备份操作
myrepl:PRIMARY> use test
myrepl:PRIMARY> for (i=1;i<1000000 ;i++){ db.magedu.insert ( { "id" :i, "name" : "shu" , "age" : 20,"date" : new Date()})}

#oplog只支持完全备份
[root@ubuntu1804 ~]#mkdir /backup/

#使用--oplog选项可以备份同时也备份oplog实现热备份,会记录备份过程中的数据变化。并以oplog.bson保存下来
[root@ubuntu1804 ~]#mongodump --oplog -o /backup/
[root@ubuntu1804 ~]#ls /backup/
admin config oplog.bson test

#查看oplog日志
[root@ubuntu1804 ~]#bsondump /backup/oplog.bson | head -n1
{"op":"i","ns":"test.magedu","ui":{"$binary":
{"base64":"hQWhnxxZRT6RqqCJKMi32g==","subType":"04"}},"o":{"_id":
{"$oid":"6195b8594414c155d4825e15"},"id":{"$numberDouble":"5891.0"},"name
":"shu","age":{"$numberDouble":"20.0"},"date":{"$date":
{"$numberLong":"1637202009082"}}},"ts":{"$timestamp":
{"t":1637202009,"i":60}},"t":{"$numberLong":"1"},"v":{"$numberLong":"2"},"wall":
{"$date":{"$numberLong":"1637202009082"}}}
2021-11-18T11:11:00.247+0800 5 objects found
2021-11-18T11:11:00.248+0800 write /dev/stdout: broken pipe
[root@ubuntu1804 ~]#mongo

#查看所有操作的oplog
myrepl:PRIMARY>use local
myrepl:PRIMARY>db.oplog.rs.find().pretty()

#查看创建操作的oplog,op的i表示insert,u表示update,d表示delete,c表示ddl,n表示note
myrepl:PRIMARY>db.oplog.rs.find({op: "c"}).pretty()

#备份完成后删除表magedu
[root@ubuntu1804 ~]#mongo
myrepl:PRIMARY>use test
myrepl:PRIMARY>db.magedu.drop()

#不使用oplog恢复，查看数据数量
[root@ubuntu1804 ~]#mongorestore --drop /backup
[root@ubuntu1804 ~]#mongo
>my_repl:PRIMARY> db.magedu.count()
#使用oplog恢复，查看数据数量，和上面比较
[root@ubuntu1804 ~]#mongorestore --drop --oplogReplay /backup
[root@ubuntu1804 ~]#mongo
>myrepl:PRIMARY> db.magedu.count()

故障说明:
每天3点全备，oplog恢复窗口为48小时
上午10点test库的vast业务表被误删除。
恢复过程:
1、停应用
2、找测试库
3、恢复昨天晚上全备
4、截取全备之后到test.vast被误删除时间点的oplog
5、恢复到测试库
6、将误删除表导出，恢复到生产库

1)完全备份
mongo
myrepl:PRIMARY> use test
myrepl:PRIMARY> for (i=0;i<100 ;i++){ db.vast.insert ( { "id" :i, "name" :"shu" , "age" : 20,"date" : new Date()})}

#执行完全备份
mkdir -p /backup/full
mongodump --oplog -o /backup/full
ls /backup/full/
admin config oplog.bson test

2)模拟数据变化
mongo
myrepl:PRIMARY> db.test1.insert({id:1})
myrepl:PRIMARY> db.test2.insert({name:"wang"})
myrepl:PRIMARY> show tables
test1
test2
vast

3)模拟10:00误删除test库中的vast表
myrepl:PRIMARY> db.vast.drop()
myrepl:PRIMARY> show tables
test1
test2
#开始恢复,先停应用后,执行下面恢复过程

4)备份当前oplog.rs表即备份最新oplog
mongodump -d local -c oplog.rs -o /backup/oplog
tree /backup/oplog/
/backup/oplog/
└── local
├── oplog.rs.bson
└── oplog.rs.metadata.json
1 directory, 2 files

5)将备份下来的oplog的bson文件,覆盖完全备份的oplog.bson文件,用来还原
cp /backup/oplog/local/oplog.rs.bson /backup/full/oplog.bson

6)查看local库的oplog.rs表获取误删除vast表的时间戳
myrepl:PRIMARY> use local
myrepl:PRIMARY> db.oplog.rs.find({op:"c"}).pretty()
#查看到误删除vast表的记录如下,记下ts信息
.....
{
"op" : "c",
"ns" : "test.$cmd",
"ui" : UUID("db7e9d49-d965-42ad-9134-863d723cbbd6"),
"o" : {
"drop" : "vast"
},
"o2" : {
"numRecords" : 99
},
"ts" : Timestamp(1574251087, 1), #此行需要记录下来
"t" : NumberLong(1),
"v" : NumberLong(2),
"wall" : ISODate("2019-11-20T11:58:07.223Z")
}

7)利用oplog恢复备份至误删除时间点
mongorestore --oplogReplay --oplogLimit "1574251087:1" --drop /backup/full/

8)验证是否恢复
myrepl:PRIMARY> use test
myrepl:PRIMARY> show tables;
test1
test2
vast
myrepl:PRIMARY> db.vast.count()
100