Mongodb副本集副本集是什么
– MongoDB
复制是将数据同步在多个服务器的过程。
–
复制提供了数据的冗余备份,并在多个服务器上存储数据副本,提高了数据的可用性, 并可以保证数据的安全性。
–
复制还允许您从硬件故障和服务中断中恢复数据
1)
清空从库数据
[root@host53 etc]# rm -rf /usr/local/mongodb/data/db/*
2
）启动副本集（都要配置）启动服务时,指定主机所在副本集名称
–
副本集成员间使用相同的副本集名称
– --replSet rs1 //
指定副本集名称
[root@host53 etc]# rm -rf /usr/local/mongodb/data/db/*
[root@host53 etc]# vim mongodb.conf
[root@host53 etc]# tail -1 mongodb.conf
replSet=rs1 ###S
大写
3
）创建副本集(任意一台进入mongodb创建)
config={
_id:"rs1",
members:[
{_id:0,host:"192.168.4.51:27051"},
{_id:1,host:"192.168.4.52:27052"},
{_id:2,host:"192.168.4.53:27053"},
]
};
######{_id:0,host:"192.168.4.51:27051",priority:10},##priority:10
指定优先级，优先级越高的做主
{ ###
这是输出
"_id" :"rs1",
"members" : [
{
"_id" : 0,
"host" :"192.168.4.51:27051"
},
{
"_id" : 1,
"host" :"192.168.4.52:27052"
},
{
"_id" : 2,
"host" :"192.168.4.53:27053"
}
]
}
初始化 Replica Sets 环境
•
执行如下命令
– >rs.initiate(config)
{
"ok" : 1,
"operationTime" :Timestamp(1531101358, 1),
"$clusterTime" : {
"clusterTime" :Timestamp(1531101358, 1),
"signature" : {
"hash" :BinData(0,"AAAAAAAAAAAAAAAAAAAAAAAAAAA="),
"keyId" :NumberLong(0)
}
}
}
######
想让水成为master就在谁上执行创建集群的命令
查看副本集信息
•
查看状态信息
– > rs.status( )
•
查看是否是 master 库
– > rs .isMaster( )
测试副本集
验证副本集配置
•
同步数据验证
rs1:PRIMARY> use gamedb
switched to db gamedb
rs1:PRIMARY> db
gamedb
rs1:PRIMARY> db.c1.save({name:"bob",age:19})
WriteResult({ "nInserted" : 1 })
rs1:PRIMARY> db.c1.find()
{ "_id" : ObjectId("5b42c904f84e7d5e5f048b7f"),"name" : "bob", "age" : 19 }
rs1:PRIMARY>
– >db.getMongo( ).setSlaveOk( )
允许从库查看数据 从库不输入这个命令不能操作的
rs1:SECONDARY> use gamedb
switched to db gamedb
rs1:SECONDARY> show tables
c1
rs1:SECONDARY> db.c1.find()
{ "_id" : ObjectId("5b42c904f84e7d5e5f048b7f"),"name" : "bob", "age" : 19 }
rs1:SECONDARY>
down
掉51测试集群高可用
rs1:SECONDARY> rs.isMaster()
{
"hosts" : [
"192.168.4.51:27051",
"192.168.4.52:27052",
"192.168.4.53:27053"
],
"setName" :"rs1",
"setVersion" : 1,
"ismaster" : true,
"secondary" : false,
"primary" :"192.168.4.52:27052", ####52
为主
"me" :"192.168.4.52:27052",
save( )
•
格式
– db.
集合名 .save({ key:“ 值”,
key:” 值” })
•
注意
–
集合不存在时创建集合,后插入记录
– _id
字段值 已存在时 修改文档字段值 ####与insert区别
– _id
字段值 不已存在时 插入文档
insert()
•
格式
– db.
集合名 .insert({key:“ 值”,
key:” 值” })
•
注意
–
集合不存在时创建集合,后插入记录
– _id
字段值 已存在时放弃插入
– _id
字段值 不已存在时 插入文档
save insert
一次只能插入一条记录
> db.c5.save({_id:17,name:"bob",age:55})####
指定了ID，id相同才算同一条纪律
WriteResult({ "nMatched" : 0, "nUpserted" : 1,"nModified" : 0, "_id" : 17 })
> db.c5.save({_id:17,name:"bob",age:44})
WriteResult({ "nMatched" : 1, "nUpserted" : 0,"nModified" : 1 })
> db.c5.find()
{ "_id" : ObjectId("5b42d871db9ecee350432c16"),"name" : "bob", "age" : 66 }
{ "_id" : ObjectId("5b42d879db9ecee350432c17"),"name" : "bob", "age" : 55 }
{ "_id" : 17, "name" : "bob", "age" :44 }
> db.c5.save({_id:17,name:"bob",age:33})
WriteResult({ "nMatched" : 1, "nUpserted" : 0,"nModified" : 1 })
> db.c5.find()
{ "_id" : ObjectId("5b42d871db9ecee350432c16"),"name" : "bob", "age" : 66 }
{ "_id" : ObjectId("5b42d879db9ecee350432c17"),"name" : "bob", "age" : 55 }
{ "_id" : 17, "name" : "bob", "age" :33 }
> db.c5.insert({_id:17,name:"bj",age:33}) ###
只认id字段值
WriteResult({
"nInserted" : 0,
"writeError" : {
"code" : 11000,
"errmsg" : "E11000duplicate key error collection: test.c5 index: _id_ dup key: { : 17.0}"
}
> db.c6.insertMany([{name:'tom',age:18},{name:'xie',school:'tarena'}])
一次插入多条纪律，注意有中括号
##############
{
"acknowledged" : true,
"insertedIds" : [
ObjectId("5b42da40db9ecee350432c18"),
ObjectId("5b42da40db9ecee350432c19")
]
}
查询语法
•
显示所有行,默认一次只输出 20 行 输入 it 显示后续的行
– db.
集合名.find()
•
显示第 1 行
– > db.
集合名.findOne()
•
指定查询条件并指定显示的字段
– > db.
集合名 .find ( { 条件 },{定义显示的字段} )
– > db.user.find({},{_id:0,name:1,shell:1})
– 0
不显示 1 显示
> db.c3.find({uid:1})
{ "_id" : ObjectId("5b408b7343bc8ff8b489ac08"),"name" : "bin", "password" : "x","uid" : 1, "gid" : 1, "comment" :"bin", "homedir" : "/bin", "shell" :"/sbin/nologin" }
> db.c3.find({uid:1},{_id:0})
{ "name" : "bin", "password" : "x","uid" : 1, "gid" : 1, "comment" :"bin", "homedir" : "/bin", "shell" :"/sbin/nologin" }
> db.c3.find({uid:2},{_id:0})
{ "name" : "daemon", "password" : "x","uid" : 2, "gid" : 2, "comment" :"daemon", "homedir" : "/sbin", "shell": "/sbin/nologin" }
> db.c3.find({uid:2},{name:1,uid:1})
{ "name" : "daemon", "uid" : 2 }
行数显示限制
• limit(
数字 ) // 显示前几行
> db.
集合名.find().limit(3)
skip(
数字)
//
跳过前几行
– > db.
集合名.find().skip(2)
• sort(
字段名 ) // 排序
– > db.
集合名.find().sort(age:1|-1) 1:升序 ,-1:降序
– > db.user.find({shell:"/sbin/nologin"},{_id:0,name:1,uid:
1,shell:1}).skip(2).limit(2)
> db.c3.find({},{_id:0,name:1,uid:1}).sort({uid:-1})
{ "name" : "yaya", "uid" : 888888 }
{ "name" : "nfsnobody", "uid" : 65534 }
{ "name" : "lisi", "uid" : 1000 }
{ "name" : "polkitd", "uid" : 999 }
– db.
集合名 .find({key:” 值”})
– db.
集合名 .find({key:” 值”,
keyname:” 值” })
> db.c3.find({name:"root"},{_id:0,name:1})
{ "name" : "root" }
> db.c3.find({name:"root",uid:0},{_id:0,name:1})
两个条件同时成立
{ "name" : "root" }
•
范围比较
– $in
在...里
– $nin
不在...里
– $or
或
– > db.user.find({uid:{$in:[1,6,9]}})
– > db.user.find({uid:{$nin:[1,6,9]}})
– > db.user.find({$or: [{name:"root"},{uid:1} ]})
> db.c3.find({ uid:{$in: [1,6,9]} },{_id:0,uid:1})
{ "uid" : 1 }
{ "uid" : 6 }
>
> db.c3.find({name:{$in:['root','daemon','bin']}},{_id:0,name:1})
{ "name" : "root" }
{ "name" : "bin" }
{ "name" : "daemon" }
>db.c3.find({shell:{$nin:['/bin/bash','/sbin/nologin']}},{_id:0,name:1,shell:1})
{ "name" : "sync", "shell" :"/bin/sync" }
{ "name" : "shutdown", "shell" : "/sbin/shutdown"}
{ "name" : "halt", "shell" :"/sbin/halt" }
{ "name" : "mysql", "shell" :"/bin/false" }
>
> db.c3.find({$or:[{name:'root'},{name:'mysql'}]},{_id:0,name:1})
{ "name" : "root" }
{ "name" : "mysql" }
>
•
正则匹配
– > db.user.find({name: /^a/ })
数值比较
– $lt $lte $gt $gte $ne
< <= > >= !=
– db.user.find( { uid: { $gte:10,$lte:40} } , {_id:0,name
:1,uid:1})
– db.user.find({uid:{$lte:5,}})
> db.c3.find({name:/^a/},{name:1,_id:0})
{ "name" : "adm" }
{ "name" : "abrt" }
{ "name" : "avahi" }
{ "name" : "apache" }
> db.c3.find({uid:{$gte:10,$lte:40}},{_id:0,name:1,uid:1})
{ "name" : "operator", "uid" : 11 }
{ "name" : "games", "uid" : 12 }
{ "name" : "ftp", "uid" : 14 }
{ "name" : "rpc", "uid" : 32 }
{ "name" : "rpcuser", "uid" : 29 }
{ "name" : "ntp", "uid" : 38 }
{ "name" : "mysql", "uid" : 27 }
>db.c3.find({uid:{$gte:10,$lte:40}},{_id:0,name:1,uid:1}).sort({uid:1})
{ "name" : "operator", "uid" : 11 }
{ "name" : "games", "uid" : 12 }
{ "name" : "ftp", "uid" : 14 }
{ "name" : "mysql", "uid" : 27 }
{ "name" : "rpcuser", "uid" : 29 }
{ "name" : "rpc", "uid" : 32 }
{ "name" : "ntp", "uid" : 38 }
>db.c3.find({uid:{$gte:10,$lte:40}},{_id:0,name:1,uid:1}).sort({uid:1}).limit(1)
{ "name" : "operator", "uid" : 11 }
•
匹配 null , 也可以匹配没有的字段
– > db.user.save({name:null,uid:null})
> db.c3.save({name:null,uid:null})
WriteResult({ "nInserted" : 1 })
> db.c3.find({name:null})
{ "_id" : ObjectId("5b430a6cdb9ecee350432c1a"),"name" : null, "uid" : null }
> db.c3.find({name:null},{_id:0})
也可以匹配没有的字段
{ "name" : null, "uid" : null }
> db.c3.find({gid:null},{_id:0})
{ "name" : null, "uid" : null }
update()
– > db.
集合名 .update({ 条件 },{修改的字段} )
注意:把文件的其他字段都删除了,只留下了 password 字段
,
且只修改与条件匹配的第 1 行!!!
$set
条件匹配时,修改指定字段的值
– db.user.update({
条件 },$set: { 修改的字段})
> db.c3.find({uid:{$lte:3}},{_id:0})
{ "name" : "root", "password" : "x","uid" : 0, "gid" : 0, "comment" :"root", "homedir" : "/root", "shell" :"/bin/bash" }
{ "name" : "bin", "password" : "x","uid" : 1, "gid" : 1, "comment" :"bin", "homedir" : "/bin", "shell" :"/sbin/nologin" }
{ "name" : "daemon", "password" : "x","uid" : 2, "gid" : 2, "comment" :"daemon", "homedir" : "/sbin", "shell": "/sbin/nologin" }
{ "name" : "adm", "password" : "x","uid" : 3, "gid" : 4, "comment" :"adm", "homedir" : "/var/adm", "shell": "/sbin/nologin" }
> db.c3.update({uid:{$lte:3}},{password:"AAA"})
WriteResult({ "nMatched" : 1, "nUpserted" : 0,"nModified" : 1 })
> db.c3.find({uid:{$lte:3}},{_id:0})
{ "name" : "bin", "password" : "x","uid" : 1, "gid" : 1, "comment" :"bin", "homedir" : "/bin", "shell" :"/sbin/nologin" }
{ "name" : "daemon", "password" : "x","uid" : 2, "gid" : 2, "comment" :"daemon", "homedir" : "/sbin", "shell": "/sbin/nologin" }
{ "name" : "adm", "password" : "x","uid" : 3, "gid" : 4, "comment" :"adm", "homedir" : "/var/adm", "shell": "/sbin/nologin" }
> db.c3.find({password:'AAA'})
{ "_id" : ObjectId("5b408b7343bc8ff8b489ac07"),"password" : "AAA" }
•
语法格式:默认只更新与条件匹配的第 1 行
– > db.user.update({
条件 },{$set:{ 修改的字段}} ,false,
true )
> db.c3.update({uid:{$lte:3}},{$set:{password:"AAA"}},false,true)
WriteResult({ "nMatched" : 3, "nUpserted" : 0,"nModified" : 3 })
> db.c3.find({uid:{$lte:3}},{_id:0})
{ "name" : "bin", "password" : "AAA","uid" : 1, "gid" : 1, "comment" :"bin", "homedir" : "/bin", "shell" :"/sbin/nologin" }
{ "name" : "daemon", "password" :"AAA", "uid" : 2, "gid" : 2, "comment": "daemon", "homedir" : "/sbin","shell" : "/sbin/nologin" }
{ "name" : "adm", "password" : "AAA","uid" : 3, "gid" : 4, "comment" :"adm", "homedir" : "/var/adm", "shell": "/sbin/nologin" }
>db.c3.update({uid:{$lte:3}},{$set:{password:"AAA",shell:"/bin/bash"}},false,true)
WriteResult({ "nMatched" : 3, "nUpserted" : 0,"nModified" : 3 })
> db.c3.find({uid:{$lte:3}},{_id:0})
{ "name" : "bin", "password" : "AAA","uid" : 1, "gid" : 1, "comment" :"bin", "homedir" : "/bin", "shell" :"/bin/bash" }
{ "name" : "daemon", "password" :"AAA", "uid" : 2, "gid" : 2, "comment": "daemon", "homedir" : "/sbin","shell" : "/bin/bash" }
{ "name" : "adm", "password" : "AAA","uid" : 3, "gid" : 4, "comment" :"adm", "homedir" : "/var/adm", "shell": "/bin/bash" }
>
$unset
删除与条件匹配文档的字段
– db.
集合名 .update({ 条件},{$unset:{key:values}})
> db.c3.update({uid:1},{$unset:{password:'F'}})
WriteResult({ "nMatched" : 1, "nUpserted" : 0,"nModified" : 1 })
$inc
条件匹配时,字段值自加或自减
– Db.
集合名 .update({ 条件},{$inc:{ 字段名 : 数字}})
正整数自加 负整数自减!!
> db.c3.update({name:'bin'},{$inc:{uid:2}})
WriteResult({ "nMatched" : 1, "nUpserted" : 0,"nModified" : 1 })
> db.c3.find({name:'bin'},{_id:0})
{ "name" : "bin", "uid" : 3, "gid" : 1,"comment" : "bin", "homedir" : "/bin","shell" : "/bin/bash" }
> db.c3.update({name:'bin'},{$inc:{uid:-2}})
WriteResult({ "nMatched" : 1, "nUpserted" : 0,"nModified" : 1 })
> db.c3.find({name:'bin'},{_id:0})
{ "name" : "bin", "uid" : 1, "gid" : 1,"comment" : "bin", "homedir" : "/bin","shell" : "/bin/bash" }
$push / $addToSet
• $push
向数组中添加新元素
– db.
集合名 .update({ 条件},{$push:{ 数组名 :“ 值” }})
– db.user.insert({name:"bob",likes:
["a","b","c","d","e","f"]})
– db.user.update({name:“bob”},{$push:{likes:“w"}})
> db.user.find()
{ "_id" : ObjectId("5b4314b5db9ecee350432c1b"),"name" : "bob", "likes" : [ "a","b", "c", "d", "e", "f","w" ] }
• $addToSet
避免重复添加
– db.
集合名 .update({ 条件},{$addToSet:{ 数组名:”
值” }})
db.user.update({name:"bob"},{$addToSet:{likes:“f"}})
> db.user.update({name:'bob'},{$addToSet:{likes:'w'}})
####
命令会执行单不会添加
WriteResult({ "nMatched" : 1, "nUpserted" : 0,"nModified" : 0 })
> db.user.find()
{ "_id" : ObjectId("5b4314b5db9ecee350432c1b"),"name" : "bob", "likes" : [ "a","b", "c", "d", "e", "f","w" ] }
$pop /$pull
• $pop
从数组头部删除一个元素
– db.
集合名 .update({ 条件},{$pop:{ 数组名 : 数字}})
– db.user.update({name:"bob"},{$pop:{likes:1}})
– db.user.update({name:"bob"},{$pop:{likes:-1}})
1
删除数组尾部元素 -1 删除数组头部元素
> db.user.update({name:'bob'},{$pop:{likes:1}})
WriteResult({ "nMatched" : 1, "nUpserted" : 0,"nModified" : 1 })
> db.user.find()
{ "_id" : ObjectId("5b4314b5db9ecee350432c1b"),"name" : "bob", "likes" : [ "a","b", "c", "d", "e", "f" ]}
> db.user.update({name:'bob'},{$pop:{likes:-1}})
WriteResult({ "nMatched" : 1, "nUpserted" : 0,"nModified" : 1 })
> db.user.find()
{ "_id" : ObjectId("5b4314b5db9ecee350432c1b"),"name" : "bob", "likes" : [ "b","c", "d", "e", "f" ] }
• $pull
删除数组指定元素
– db.
集合名 .update({ 条件},{$pull:{ 数组名 : 值}})
– db.user.update({name:"bob"},{$pull:{likes:"b"}})
> db.user.update({name:'bob'},{$pull:{likes:'e'}})
WriteResult({ "nMatched" : 1, "nUpserted" : 0,"nModified" : 1 })
> db.user.find()
{ "_id" : ObjectId("5b4314b5db9ecee350432c1b"),"name" : "bob", "likes" : [ "b","c", "d", "f" ] }
$drop/$remove
• $drop
删除集合的同时删除索引
– db.
集合名.drop( )
– db.user.drop( )
• remove()
删除文档时不删除索引
– db.
集合名 .remove({}) // 删除所有文档
– db.
集合名 .remove({ 条件 }) // 删除与条件匹配的文档
– db.user.remove({uid:{$lte:10}})
– db.user.remove({})
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