Mongodb学习笔记

brew安装

brew services stop mongodb
brew uninstall mongodb

brew tap mongodb/brew
brew install mongodb-community
brew services start mongodb-community

如遇报错BadValue: Invalid value for version, found 3.6, expected '4.2' or '4.0'.，备份并删除/usr/local/var/mongodb

基本操作

连接

mongo --host 127.0.0.1
show dbs

创建db

user school
db.school.insert({name:'为民小学',age:10});

查看删除db

db.getName()
db.dropDatabase()

查看帮助

db.school.help()

查看数据库下的集合

show collections

创建集合

db.createCollection('grade3')
db.grade1.insert({name: 'Lily', age: 8})

插入文档

db.grade1.insert({_id: '1',name: 'Han Meimei', age: 8})
db.grade1.save({_id: '1',name: 'Han Meimei', age: 9})
db.grade1.save({_id: '2',name: 'Han Meimei', age: 9})

更新文档

db.collection.update(
   <query>,
   <updateObj>,
   {
     upsert: <boolean>,
     multi: <boolean>
   }
)

db.grade1.update({name:'Tom'}, {$push: {'hobby':'reading'} })
db.grade1.update({_id:3}, {$addToSet: {friends:'huge'}})
db.grade1.update({_id:3}, {$pop:{friends: 1}})
db.grade1.update({_id:3}, {$addToSet:{friends:{$each: ['huangbo','zhangyixing']}}})
db.grade1.update({_id:3}, {$push:{friends:{$each: ['huangbo','zhangyixing']}}})
db.grade1.update({name: 'Han Meimei', hobby:{$ne:'reading'}, _id: {$ne:'2'}}, {$push: {hobby: 'drinking'}})
db.grade1.update({_id:3}, {$set:{"info11":{id:'11'}}})
db.grade1.update({name: 'Tom'}, {$unset:{'age':''}})

删除文档

db.collection.remove(
   <query>,
   {
     justOne: <boolean>
   }
)

db.grade1.remove({'name': 'Han Meimei'}, {justOne: true})
db.grade1.remove({'name': 'Han Meimei'})

查询文档

db.collection_name.find(query, projection)；

db.grade1.find()
db.grade1.find({age:{$in:[9,11]}})
db.grade1.find({age:{$nin:[9,11]}})
db.grade1.find({age:{$not:{$lt:11}}})
db.grade1.find({age:{$ne:9}})

数组的用法

db.grade1.find({"friends" : [ "Lily", "Jobs", "Lucy", "Zhang San" ]})
db.grade1.find({"friends" : [ "Lily" ]})
db.grade1.find({"friends" :{$all: ["Zhang San"]}})
db.grade1.find({"friends" :{$in: ["Zhang San"]}})

db.grade1.find({$where:'this.name == "Tom1"'})
db.grade1.find({$where: function(){return this.age == 9}})

RoboMongo

https://robomongo.org/

mysql&postgre对nosql的支持

https://juejin.im/post/5cefd68551882559685b3c1c https://learnku.com/laravel/t/13185/in-depth-understanding-of-json-data-type-of-mysql-nosql-in-relational-database https://www.oschina.net/translate/friendfeed-schemaless-mysql-new

另一种思路，mysql5.7.8+ ， postgre9.3+已经原生对nosql支持，提供json数据类型，天然就解决了动态表单受schema约束的问题 动态表单程序只需要提供mongo/mysql/postgres等多种数据源的可选项即可 对于业务系统来说，spring data对json类型支持比较好，mybatis较差需要写一些代码手工映射

参考文档

https://juejin.im/post/5add9e655188256735642122 https://juejin.im/entry/5926ca5044d9040064076569 https://segmentfault.com/a/1190000012357379 http://mysql.taobao.org/monthly/2019/03/02/ https://cloud.tencent.com/developer/article/1166593 https://www.oschina.net/translate/friendfeed-schemaless-mysql-new https://docs.mongodb.com/manual/data-modeling/