基础：
- 是非关系型数据库
- 文档存储
1、显示当前的所有数据库
- show dbs
- show databases;
2、使用数据库
- use 数据库
3、查看当前数据库
- db
4、显示数据库中所有的集合
- show collections
5、查看docker日志
- docker logs docker_mongodb(mongodb的docker容器名字)
6、Mongo Express是一个基于网络的MongoDB数据库管理界面
- docker pull mongo-express // 下载mongo-express镜像
- docker run --link docker_mongodb:mongo -p 8081:8081 mongo-express //运行mongo-express，docker_mongodb是docker中mongodb容器名字
7、mongo shell是用来操作MongoDB的javascript客户端界面
- 运行mogog shell
docker exec -it docker_mongodb mongo - exit 退出
8、数据库的CRUD(增删改查)操作
- Create、Read、Update、Delete
- 文档主键: _id
- 文档主建有唯一性
- 支出所有数据类型（除了数组）
- 自动生成主建（12字节，前四个是时间）
9、创建文档
- db.collection.insert()
1、db.insertOne() 一次只能插入一个文档db.accounts.insertOne({name:"nanzai", balance: 3500}) { "acknowledged" : true, "insertedId" : ObjectId("5e157856665014c2c50ea538") }
2、db.insertMany()必须插入多个文档db.accounts.insertMany([{name:"xinzai", balance: 500}, {name:"xinge", balance:600}]) { "acknowledged" : true, "insertedIds" : [ ObjectId("5e1576cc665014c2c50ea536"), ObjectId("5e1576cc665014c2c50ea537") ] }
3、db.collection.inset()可以插入一个或者多个文档db.accounts.insert([{name: "jack",balance: 2000, contact: ["137111111","陕西省","China"]},{name: "karen", balance: 3000, contact: ["18391000411", "湖南省", "china"]}]) BulkWriteResult({ "writeErrors" : [ ], "writeConcernErrors" : [ ], "nInserted" : 2, "nUpserted" : 0, "nMatched" : 0, "nModified" : 0, "nRemoved" : 0, "upserted" : [ ] })db.accounts.insert({name: "ke", balance: 1800, "contact": [["1754684641","195324664654"], "陕西省", "China"]}) WriteResult({ "nInserted" : 1 }) - db.collection.save()
- 创建多个文档
10、查找文档
数组操作符：all
- db.collection.find()查询所有文档
db.accounts.find() { "_id" : ObjectId("5e1331591f342ac67bb98e52"), "name" : "xiaoke", "balance" : 1000 } { "_id" : ObjectId("5e1332d11f342ac67bb98e53"), "name" : "one", "balance" : 1000 } { "_id" : ObjectId("5e13331e1f342ac67bb98e54"), "name" : "one", "balance" : 1000 } { "_id" : ObjectId("5e1336e91f342ac67bb98e57"), "name" : "jack", "balance" : 2000, "contact" : [ "137111111", "陕西省", "China" ] } { "_id" : ObjectId("5e1336e91f342ac67bb98e58"), "name" : "karen", "balance" : 3000, "contact" : [ "18391000411", "湖南省", "china" ] } { "_id" : ObjectId("5e1337dc1f342ac67bb98e59"), "name" : "xiaoke", "balance" : 1000, "contact" : [ "1371811111", "山西省", "China" ] } { "_id" : ObjectId("5e1337dc1f342ac67bb98e5a"), "name" : "xiaowang", "balance" : 1500, "contact" : [ "18891000411", "湖南省", "china" ] } - 读取联系地址位于China陕西省的银行账户信息
db.accounts.find({contact:{$all:["China","陕西省"]}}) { "_id" : ObjectId("5e1336e91f342ac67bb98e57"), "name" : "jack", "balance" : 2000, "contact" : [ "137111111", "陕西省", "China" ] } - 读取联系电话包含1754684641和195324664654的银行账户文档
db.accounts.find( { "contact":{ $all: [["1754684641", "195324664654"]]}}) { "_id" : ObjectId("5e133b15738962fb118b2554"), "name" : "ke", "balance" : 1800, "contact" : [ [ "1754684641", "195324664654" ], "陕西省", "China" ] } -
.pretty()打印的更加清楚
db.accounts.find({name: "xin"}).pretty() { "_id" : ObjectId("5e154a6d297892ae4951650d"), "name" : "xin", "balance" : 5000, "contact" : [ "1204557644", "广东省", "china" ] } { "_id" : ObjectId("5e154a79297892ae4951650e"), "name" : "xin", "balance" : 5000, "contact" : [ "1204557644", "广东省", "china" ] }
elemMatch 任一操作符
- 读取联系电话范围在“1371811111”和“195324664654”之间的银行账户文档
db.accounts.find( {contact: {$elemMatch: {$gt:"1371811111", $lt: "195324664654"}}}) { "_id" : ObjectId("5e1336e91f342ac67bb98e58"), "name" : "karen", "balance" : 3000, "contact" : [ "18391000411", "湖南省", "china" ] } { "_id" : ObjectId("5e1337dc1f342ac67bb98e5a"), "name" : "xiaowang", "balance" : 1500, "contact" : [ "18891000411", "湖南省", "china" ] }
正则表达式
- 在和$in操作符一起使用时，只能使用/pattern/<options>
- 读取用户姓名以k或者j开头的银行账户文档
db.accounts.find({name: {$in : [/^k/, /^j/]}}) { "_id" : ObjectId("5e1336e91f342ac67bb98e57"), "name" : "jack", "balance" : 2000, "contact" : [ "137111111", "陕西省", "China" ] } { "_id" : ObjectId("5e1336e91f342ac67bb98e58"), "name" : "karen", "balance" : 3000, "contact" : [ "18391000411", "湖南省", "china" ] } { "_id" : ObjectId("5e133b15738962fb118b2554"), "name" : "ke", "balance" : 1800, "contact" : [ [ "1754684641", "195324664654" ], "陕西省", "China" ] }
文档游标
- db.collection.find()返回一个文档集合游标
- 在不迭代游标的情况下，只列出前20个文档
- var myCour = db.accounts.find()
myCourvar myCourt = db.accounts.find() > myCourt { "_id" : ObjectId("5e1331591f342ac67bb98e52"), "name" : "xiaoke", "balance" : 1000 } { "_id" : ObjectId("5e1332d11f342ac67bb98e53"), "name" : "one", "balance" : 1000 } { "_id" : ObjectId("5e13331e1f342ac67bb98e54"), "name" : "one", "balance" : 1000 } { "_id" : ObjectId("5e1336e91f342ac67bb98e57"), "name" : "jack", "balance" : 2000, "contact" : [ "137111111", "陕西省", "China" ] } { "_id" : ObjectId("5e1336e91f342ac67bb98e58"), "name" : "karen", "balance" : 3000, "contact" : [ "18391000411", "湖南省", "china" ] } { "_id" : ObjectId("5e1337dc1f342ac67bb98e59"), "name" : "xiaoke", "balance" : 1000, "contact" : [ "1371811111", "山西省", "China" ] } { "_id" : ObjectId("5e1337dc1f342ac67bb98e5a"), "name" : "xiaowang", "balance" : 1500, "contact" : [ "18891000411", "湖南省", "china" ] } { "_id" : ObjectId("5e133b15738962fb118b2554"), "name" : "ke", "balance" : 1800, "contact" : [ [ "1754684641", "195324664654" ], "陕西省", "China" ] } - 我们也可以使用游标下标直接访问文档集合中的某一个文档
var myCourt = db.accounts.find() > myCourt[1] { "_id" : ObjectId("5e1332d11f342ac67bb98e53"), "name" : "one", "balance" : 1000 } - 游历完游标中所有的文档之后，或者在10分钟之后，游标便会自动关闭。
- 可以使用noCursorTimeout()函数来保持游标一直有效。
var myCursor = db.accounts.find().noCursorTimeout() myCursor.close //关闭游标 - 遍历所有文档游标
方法一：var my = db.accounts.find({ name : "one"}); > while( my.hasNext()){ printjson(my.next()) } { "_id" : ObjectId("5e1332d11f342ac67bb98e53"), "name" : "one", "balance" : 1000 } { "_id" : ObjectId("5e13331e1f342ac67bb98e54"), "name" : "one", "balance" : 1000 }方法二：
var my = db.accounts.find({ name : "one"}); > my.forEach(printjson) { "_id" : ObjectId("5e1332d11f342ac67bb98e53"), "name" : "one", "balance" : 1000 } { "_id" : ObjectId("5e13331e1f342ac67bb98e54"), "name" : "one", "balance" : 1000 } - cursor.limit(<number>)查询指定数量
db.accounts.find().limit(3) { "_id" : ObjectId("5e1331591f342ac67bb98e52"), "name" : "xiaoke", "balance" : 1000 } { "_id" : ObjectId("5e1332d11f342ac67bb98e53"), "name" : "one", "balance" : 1000 } { "_id" : ObjectId("5e13331e1f342ac67bb98e54"), "name" : "one", "balance" : 1000 }find().limit(0)和find()结果一样。
- cursor.skip(<offset>)绕过指定数量
db.accounts.find().skip(3) { "_id" : ObjectId("5e1336e91f342ac67bb98e57"), "name" : "jack", "balance" : 2000, "contact" : [ "137111111", "陕西省", "China" ] } { "_id" : ObjectId("5e1336e91f342ac67bb98e58"), "name" : "karen", "balance" : 3000, "contact" : [ "18391000411", "湖南省", "china" ] } { "_id" : ObjectId("5e1337dc1f342ac67bb98e59"), "name" : "xiaoke", "balance" : 1000, "contact" : [ "1371811111", "山西省", "China" ] } { "_id" : ObjectId("5e1337dc1f342ac67bb98e5a"), "name" : "xiaowang", "balance" : 1500, "contact" : [ "18891000411", "湖南省", "china" ] } { "_id" : ObjectId("5e133b15738962fb118b2554"), "name" : "ke", "balance" : 1800, "contact" : [ [ "1754684641", "195324664654" ], "陕西省", "China" ] } - curor.count(<applySkipLimit>)
默认情况下，<applySkipLimit>为false，既cursor.count()不会考虑cursor.skip()和cursor.limit()的效果db.accounts.find().limit(1).count() 8 > db.accounts.find().limit(1).count(true) 1 - cursor.sort(<document>)
这里的<document>定义了排序的要求， 1表示由小及大的正向排序， -1 为逆向序 - 按照余额从大到小，用户姓名按字母排序的方式排列银行账户文档
db.accounts.find().sort({balance: -1, name: 1}) { "_id" : ObjectId("5e1336e91f342ac67bb98e58"), "name" : "karen", "balance" : 3000, "contact" : [ "18391000411", "湖南省", "china" ] } { "_id" : ObjectId("5e1336e91f342ac67bb98e57"), "name" : "jack", "balance" : 2000, "contact" : [ "137111111", "陕西省", "China" ] } { "_id" : ObjectId("5e133b15738962fb118b2554"), "name" : "ke", "balance" : 1800, "contact" : [ [ "1754684641", "195324664654" ], "陕西省", "China" ] } { "_id" : ObjectId("5e1337dc1f342ac67bb98e5a"), "name" : "xiaowang", "balance" : 1500, "contact" : [ "18891000411", "湖南省", "china" ] } { "_id" : ObjectId("5e1332d11f342ac67bb98e53"), "name" : "one", "balance" : 1000 } { "_id" : ObjectId("5e13331e1f342ac67bb98e54"), "name" : "one", "balance" : 1000 } { "_id" : ObjectId("5e1331591f342ac67bb98e52"), "name" : "xiaoke", "balance" : 1000 } { "_id" : ObjectId("5e1337dc1f342ac67bb98e59"), "name" : "xiaoke", "balance" : 1000, "contact" : [ "1371811111", "山西省", "China" ] } - 读取余额最大的银行账户文档
db.accounts.find().sort({balance:-1}).limit(1) { "_id" : ObjectId("5e1336e91f342ac67bb98e58"), "name" : "karen", "balance" : 3000, "contact" : [ "18391000411", "湖南省", "china" ] } - skip()在limit()之前执行
db.accounts.find().limit(5).skip(3) { "_id" : ObjectId("5e1336e91f342ac67bb98e57"), "name" : "jack", "balance" : 2000, "contact" : [ "137111111", "陕西省", "China" ] } { "_id" : ObjectId("5e1336e91f342ac67bb98e58"), "name" : "karen", "balance" : 3000, "contact" : [ "18391000411", "湖南省", "china" ] } { "_id" : ObjectId("5e1337dc1f342ac67bb98e59"), "name" : "xiaoke", "balance" : 1000, "contact" : [ "1371811111", "山西省", "China" ] } { "_id" : ObjectId("5e1337dc1f342ac67bb98e5a"), "name" : "xiaowang", "balance" : 1500, "contact" : [ "18891000411", "湖南省", "china" ] } { "_id" : ObjectId("5e133b15738962fb118b2554"), "name" : "ke", "balance" : 1800, "contact" : [ [ "1754684641", "195324664654" ], "陕西省", "China" ] } db.accounts.find().skip(3).limit(5) { "_id" : ObjectId("5e1336e91f342ac67bb98e57"), "name" : "jack", "balance" : 2000, "contact" : [ "137111111", "陕西省", "China" ] } { "_id" : ObjectId("5e1336e91f342ac67bb98e58"), "name" : "karen", "balance" : 3000, "contact" : [ "18391000411", "湖南省", "china" ] } { "_id" : ObjectId("5e1337dc1f342ac67bb98e59"), "name" : "xiaoke", "balance" : 1000, "contact" : [ "1371811111", "山西省", "China" ] } { "_id" : ObjectId("5e1337dc1f342ac67bb98e5a"), "name" : "xiaowang", "balance" : 1500, "contact" : [ "18891000411", "湖南省", "china" ] } { "_id" : ObjectId("5e133b15738962fb118b2554"), "name" : "ke", "balance" : 1800, "contact" : [ [ "1754684641", "195324664654" ], "陕西省", "China" ] } - sort()在skip()和limit()之前执行
db.accounts.find().sort({balance: -1 }).skip(3).limit(5) { "_id" : ObjectId("5e1336e91f342ac67bb98e58"), "name" : "karen", "balance" : 3000, "contact" : [ "18391000411", "湖南省", "china" ] } { "_id" : ObjectId("5e1336e91f342ac67bb98e57"), "name" : "jack", "balance" : 2000, "contact" : [ "137111111", "陕西省", "China" ] } { "_id" : ObjectId("5e133b15738962fb118b2554"), "name" : "ke", "balance" : 1800, "contact" : [ [ "1754684641", "195324664654" ], "陕西省", "China" ] } { "_id" : ObjectId("5e1337dc1f342ac67bb98e5a"), "name" : "xiaowang", "balance" : 1500, "contact" : [ "18891000411", "湖南省", "china" ] } { "_id" : ObjectId("5e1331591f342ac67bb98e52"), "name" : "xiaoke", "balance" : 1000 } - {field: inclusion} 1表示返回字段，0表示不返回字段
- 只返回银行账户文档中的用户姓名（不返回文档主建）
db.accounts.find({},{_id:0,name: 1}) { "name" : "xiaoke" } { "name" : "one" } { "name" : "one" } { "name" : "jack" } { "name" : "karen" } { "name" : "xiaoke" } { "name" : "xiaowang" } { "name" : "ke" } { "name" : "xin" } { "name" : "xin" } { "name" : "xinzai" } { "name" : "xinge" } { "name" : "nanzai" } - 不返回银行账户文档中的用户姓名（也不返回文档主键）
db.accounts.find({},{name:0,_id: 0}) { "balance" : 1000 } { "balance" : 1000 } { "balance" : 1000 } { "balance" : 2000, "contact" : [ "137111111", "陕西省", "China" ] } { "balance" : 3000, "contact" : [ "18391000411", "湖南省", "china" ] } { "balance" : 1000, "contact" : [ "1371811111", "山西省", "China" ] } { "balance" : 1500, "contact" : [ "18891000411", "湖南省", "china" ] } { "balance" : 1800, "contact" : [ [ "1754684641", "195324664654" ], "陕西省", "China" ] } { "balance" : 5000, "contact" : [ "1204557644", "广东省", "china" ] } { "balance" : 5000, "contact" : [ "1204557644", "广东省", "china" ] } { "balance" : 500 } { "balance" : 600 } { "balance" : 3500 } - 除了_id以外，只能查询所有返回、或者所有不返回的结果、不能两者同时查询
db.accounts.find({},{name:0,_id: 0, balance: 1}) Error: error: { "ok" : 0, "errmsg" : "Projection cannot have a mix of inclusion and exclusion.", "code" : 2, "codeName" : "BadValue" } - （有疑问，为什么我的$slide的值被解析成double了）$slice操作符可以返回数组字段中的部分元素()
db.accounts.find({},{_id: 0 , name:1, contact: { $slide: 2}}) Error: error: { "ok" : 0, "errmsg" : "Unsupported projection option: contact: { $slide: 2.0 }", "code" : 2, "codeName" : "BadValue" } - $elemMatch和$操作符可以返回数组字段中满足筛选条件的第一个元素
db.accounts.find({},{_id: 0 , name:1, contact: { $elemMatch:{$gt: "湖南省"}}}) { "name" : "xiaoke" } { "name" : "one" } { "name" : "one" } { "name" : "jack", "contact" : [ "陕西省" ] } { "name" : "karen" } { "name" : "xiaoke" } { "name" : "xiaowang" } { "name" : "ke", "contact" : [ "陕西省" ] } { "name" : "xin" } { "name" : "xin" } { "name" : "xinzai" } { "name" : "xinge" } { "name" : "nanzai" }
更新文档
- db.collection.update()
- db.<collection>.update(<query>, <update>, <options>)
<query>文档定义了更新操作时筛选文档的条件
<update>文档提供了更新的内容
<options>文档声明了一些更新操作的参数 - 如果<update>文档不包含任何更新操作符，db.collection.update()将会使用<update>文档直接替换集合中符合<qurey>文档筛选条件的文档
- 将jack的账户余额更改为“1950” （<update>中必须带name,负责就会改空）
db.accounts.update({name:"jack"},{name:"jack",balance:1950}) WriteResult({ "nMatched" : 1, "nUpserted" : 0, "nModified" : 1 }) -
任何情况下_id字段不会被更改
-
在使用<update>文档替换整篇被更新文档时，只有第一篇符合<query>文档筛选条件的文档会被更新
-
查看余额在1000到1900之间的账户文档
b.accounts.update({balance:{$gt:1000, $lt:1900}}, {name:"bill", balance:1700, gender: "M"}) //update条件有多个结果，只有第一篇文档被更新 WriteResult({ "nMatched" : 1, "nUpserted" : 0, "nModified" : 1 }) -
文档更新操作符
$set 更新或新增字段
$unset 删除字段
$rename 重命名字段
$inc 加减字段值
$mul 想乘字段值
$min 比较减小字段值
$max 比较增大字段值 -
$set操作符
-
更新karen的开户余额和信息。
db.accounts.update({name:"karen"},{$set: {balance:2500, info:{ dateOpened: new Date("2020-1-9 15:05:05"), branch: "branch1"}}}) WriteResult({ "nMatched" : 1, "nUpserted" : 0, "nModified" : 1 }) > db.accounts.find({name: "karen"}).pretty() { "_id" : ObjectId("5e1336e91f342ac67bb98e58"), "name" : "karen", "balance" : 2500, "contact" : [ "18391000411", "湖南省", "china" ], "info" : { "dateOpened" : ISODate("2020-01-09T15:05:05Z"), "branch" : "branch1" } } -
更新karen的银行账户的开户时间（更新内嵌文档的字段）
db.accounts.update({name:"jack"},{$set:{ "info.dateOpened":new Date("2029-9-9 15:05:05")}}) WriteResult({ "nMatched" : 1, "nUpserted" : 0, "nModified" : 1 }) -
更新karen账户信息中的电话号码
db.accounts.update({name:"karen"},{$set:{ "contact.0": "1777777777777"}}) WriteResult({ "nMatched" : 1, "nUpserted" : 0, "nModified" : 1 }) > db.accounts.find({name: "karen"}).pretty() { "_id" : ObjectId("5e1336e91f342ac67bb98e58"), "name" : "karen", "balance" : 2500, "contact" : [ "1777777777777", "湖南省", "china" ], "info" : { "dateOpened" : ISODate("2020-01-09T15:05:05Z"), "branch" : "branch1" } }1
-
$set更新的相同条件的文档，只会更改第一个
db.accounts.update({name: "one"}, {$set: { "balance" : 500}}) WriteResult({ "nMatched" : 1, "nUpserted" : 0, "nModified" : 1 }) > db.accounts.find() //只将name为one的第一个balance余额修改了 { "_id" : ObjectId("5e1331591f342ac67bb98e52"), "name" : "xiaoke", "balance" : 1000 } { "_id" : ObjectId("5e1332d11f342ac67bb98e53"), "name" : "one", "balance" : 500 } { "_id" : ObjectId("5e13331e1f342ac67bb98e54"), "name" : "one", "balance" : 1000 } { "_id" : ObjectId("5e1336e91f342ac67bb98e57"), "info" : "jack", "contact" : { "0" : "1777777777777" } } { "_id" : ObjectId("5e1336e91f342ac67bb98e58"), "name" : "karen" } { "_id" : ObjectId("5e1337dc1f342ac67bb98e59"), "name" : "xiaoke", "balance" : 1000, "contact" : [ "1371811111", "山西省", "China" ] } { "_id" : ObjectId("5e1337dc1f342ac67bb98e5a"), "name" : "bill", "balance" : 1700, "gender" : "M" } { "_id" : ObjectId("5e133b15738962fb118b2554"), "name" : "ke", "balance" : 1800, "contact" : [ [ "1754684641", "195324664654" ], "陕西省", "China" ] } { "_id" : ObjectId("5e154a6d297892ae4951650d"), "name" : "kx", "balance" : 5000, "contact" : [ "1204557644", "广东省", "china" ] } { "_id" : ObjectId("5e154a79297892ae4951650e"), "name" : "xin", "balance" : 5000, "contact" : [ "1204557644", "广东省", "china" ] } { "_id" : ObjectId("5e1576cc665014c2c50ea536"), "name" : "xinzai", "balance" : 500 } { "_id" : ObjectId("5e1576cc665014c2c50ea537"), "name" : "xinge", "balance" : 600 } { "_id" : ObjectId("5e157856665014c2c50ea538"), "name" : "nanzai", "balance" : 3500 } -
添加jack的联系方式（如果向现有数组字段范围以外的位置添加新值，数组字段的长度就会扩大，未被复制的数组成员将被设置为null）
db.accounts.update({name: "karen"},{$set:{"contact.4": "new contact4"}}) WriteResult({ "nMatched" : 1, "nUpserted" : 0, "nModified" : 1 }) > db.accounts.find({name: "karen"}).pretty() { "_id" : ObjectId("5e1336e91f342ac67bb98e58"), "name" : "karen", "balance" : 2500, "contact" : [ "1777777777777", "湖南省", "china", null, "new contact4" ], "info" : { "dateOpened" : ISODate("2020-01-09T15:05:05Z"), "branch" : "branch1" } }
-
删除字段 $unset
-
删除karen的银行账户余额和开户地点
db.accounts.update({name: "karen"}, {$unset: {balance:"", "info.branch": ""}}) WriteResult({ "nMatched" : 1, "nUpserted" : 0, "nModified" : 1 }) > db.accounts.find({name: "karen"}).pretty() { "_id" : ObjectId("5e1336e91f342ac67bb98e58"), "name" : "karen", "contact" : [ "1777777777777", "湖南省", "china", null, "new contact4" ], "info" : { "dateOpened" : ISODate("2020-01-09T15:05:05Z") } }说明：$unset命令中的赋值("")对操作结果并没有任何影响。既里面填写与空着都会删除该字段。
-
删除数组内的字段$unset
-
删除jack的联系电话
db.accounts.update({name:"karen"}, {$unset: {"contact.0":""}}) WriteResult({ "nMatched" : 1, "nUpserted" : 0, "nModified" : 1 }) > db.accounts.find({name: "karen"}).pretty() { "_id" : ObjectId("5e1336e91f342ac67bb98e58"), "name" : "karen", "contact" : [ null, "湖南省", "china", null, "new contact4" ], "info" : { "dateOpened" : ISODate("2020-01-09T15:05:05Z") } }说明：当时用$unset命令删除数组字段中的某一个元素时，这个元素不会被删除，只会被赋值null值，而数组的长度不会改变。
-
重命名字段$rename
说明：如果$rename命令要重命名的字段并不存在，那么文档内容不被改变
db.accounts.update({name: "karen"},{$rename:{"notExist": "notExist"}}) WriteResult({ "nMatched" : 0, "nUpserted" : 0, "nModified" : 0, "writeError" : { "code" : 2, "errmsg" : "The source and target field for $rename must differ: notExist: \"notExist\"" } }) -
如果新的字段名已经存在，那么原有的这个字段就会被覆盖掉。
// 查看name为jack db.accounts.find({name:"jack"}).pretty() { "_id" : ObjectId("5e1336e91f342ac67bb98e57"), "name" : "jack", "info" : { "dateOpened" : ISODate("2029-09-09T15:05:05Z") }, "contact" : { "0" : "1777777777777" } } // 重命名字段name 为info db.accounts.update({name:"jack"}, {$rename: {name:"info"}}) WriteResult({ "nMatched" : 1, "nUpserted" : 0, "nModified" : 1 }) //查看info为jack, 原来的info被覆盖掉了 db.accounts.find({info:"jack"}).pretty() { "_id" : ObjectId("5e1336e91f342ac67bb98e57"), "info" : "jack", "contact" : { "0" : "1777777777777" } }说明：当$rename命令中的新字段存在的时候，$rename命令会先$unset新旧字段，然后在$set新字段
-
更新kx的银行账户的开户时间和联系方式
db.accounts.update({name: "kx"}, {$set:{info:{ dateOpene: new Date("2020年1月9日17:55:38"), branch: "branch1"}, "contact.3":{ primaryEmail: "[email protected]", secondaryEmail: "[email protected]"} }}) WriteResult({ "nMatched" : 1, "nUpserted" : 0, "nModified" : 1 }) db.accounts.find({name: "kx"}).pretty() { "_id" : ObjectId("5e154a6d297892ae4951650d"), "name" : "kx", "balance" : 5000, "contact" : [ "1204557644", "广东省", "china", { "primaryEmail" : "[email protected]", "secondaryEmail" : "[email protected]" } ], "info" : { "dateOpene" : ISODate("1970-01-01T00:00:00Z"), "branch" : "branch1" } } -
更改kx的联系方式 （重命名数组中内嵌文档的字段）
-
更新账户余额和开户地点字段在文档中的位置
db.accounts.update({name: "kx"}, { $rename : {"info.dateOpene" : "date", "branch" : "branch2"}}) WriteResult({ "nMatched" : 1, "nUpserted" : 0, "nModified" : 1 }) db.accounts.find({name : "kx"}).pretty() { "_id" : ObjectId("5e154a6d297892ae4951650d"), "name" : "kx", "balance" : 5000, "contact" : [ [ "44444", "55555" ], "广东省", "china", { "primaryEmail" : "[email protected]", "secondaryEmail" : "[email protected]" } ], "info" : { "branch" : "branch1" }, "date" : ISODate("1970-01-01T00:00:00Z") } -
$rename命令中的旧字段和新字段都不可以指向数组元素
db.accounts.update({name: "kx"}, {$rename: {"contact.3.primaryEmail" : "email"}}) WriteResult({ "nMatched" : 0, "nUpserted" : 0, "nModified" : 0, "writeError" : { "code" : 2, "errmsg" : "The source field cannot be an array element, 'contact.3.primaryEmail' in doc with _id: ObjectId('5e154a6d297892ae4951650d') has an array field called 'contact'" } }) -
$rename命令中的就自断和新字段都不可以指向数组元素
这一点和之前介绍过的$set和$unset命令不同
db.accounts.find({name : "kx"}).pretty() { "_id" : ObjectId("5e154a6d297892ae4951650d"), "name" : "kx", "balance" : 5000, "contact" : [ [ "44444", "55555" ], "广东省", "china", { "primaryEmail" : "[email protected]", "secondaryEmail" : "[email protected]" } ], "info" : { "branch" : "branch1" }, "date" : ISODate("1970-01-01T00:00:00Z") } > db.accounts.update({name:"kx"}, {$rename : {"branch": "contact.3.aa"}}) WriteResult({ "nMatched" : 1, "nUpserted" : 0, "nModified" : 0 }) > db.accounts.update({name:"kx"}, {$rename : {"branch": "contact.3.secondaryEmail"}}) WriteResult({ "nMatched" : 1, "nUpserted" : 0, "nModified" : 0 }) //实际一点都没有改变 > db.accounts.find({name : "kx"}).pretty() { "_id" : ObjectId("5e154a6d297892ae4951650d"), "name" : "kx", "balance" : 5000, "contact" : [ [ "44444", "55555" ], "广东省", "china", { "primaryEmail" : "[email protected]", "secondaryEmail" : "[email protected]" } ], "info" : { "branch" : "branch1" }, "date" : ISODate("1970-01-01T00:00:00Z") } -
加 乘 操作符 $inc 、$mul
-
查看david的银行账户文档
db.accounts.find({name : "david"}) { "_id" : ObjectId("5e18592d49c9a0cf0c03948f"), "name" : "david", "balance" : 200 } -
更新david的账户余额（$inc 在原来的余额基础上加上-0.5）
db.accounts.update({name: "david"}, {$inc: {balance: -0.5}}) WriteResult({ "nMatched" : 1, "nUpserted" : 0, "nModified" : 1 }) > db.accounts.find({name : "david"}) { "_id" : ObjectId("5e18592d49c9a0cf0c03948f"), "name" : "david", "balance" : 199.5 } -
更新david的账户余额($mul在原来的余额基础上乘以0.5)
db.accounts.find({name : "david"}) { "_id" : ObjectId("5e18592d49c9a0cf0c03948f"), "name" : "david", "balance" : 200 } > db.accounts.update({name: "david"}, {$mul: {balance: 0.5}}) WriteResult({ "nMatched" : 1, "nUpserted" : 0, "nModified" : 1 }) > db.accounts.find({name : "david"}) { "_id" : ObjectId("5e18592d49c9a0cf0c03948f"), "name" : "david", "balance" : 100 }说明：$inc和$mul命令只能应用在数字字段上
-
比较大小操作符 $min $max
-
更新karen的账户余额
说明：$min 和$max操作符会和原来的数据先做比较，如果元数据符合条件则不更新，如果不符合，则更新。db.accounts.update({name: "kx"}, {$max: {balance: 6000}}) WriteResult({ "nMatched" : 1, "nUpserted" : 0, "nModified" : 1 }) > db.accounts.find({name : "kx"}) { "_id" : ObjectId("5e154a6d297892ae4951650d"), "name" : "kx", "balance" : 6000, "contact" : [ [ "44444", "55555" ], "广东省", "china", { "primaryEmail" : "[email protected]", "secondaryEmail" : "[email protected]" } ], "info" : { "branch" : "branch1" }, "date" : ISODate("1970-01-01T00:00:00Z") } > db.accounts.update({name: "kx"}, {$max: {balance: 5000}}) WriteResult({ "nMatched" : 1, "nUpserted" : 0, "nModified" : 0 }) -
如果被更新的值不存在，则会添加上去
db.accounts.find({name : "kx"}) { "_id" : ObjectId("5e154a6d297892ae4951650d"), "name" : "kx", "balance" : 6000, "contact" : [ [ "44444", "55555" ], "广东省", "china", { "primaryEmail" : "[email protected]", "secondaryEmail" : "[email protected]" } ], "info" : { "branch" : "branch1" }, "date" : ISODate("1970-01-01T00:00:00Z") } //用$max更新没有的字段上去 db.accounts.update({name: "kx"}, {$max: {money: 5000}}) WriteResult({ "nMatched" : 1, "nUpserted" : 0, "nModified" : 1 }) db.accounts.find({name: "kx"}) { "_id" : ObjectId("5e154a6d297892ae4951650d"), "name" : "kx", "balance" : 6000, "contact" : [ [ "44444", "55555" ], "广东省", "china", { "primaryEmail" : "[email protected]", "secondaryEmail" : "[email protected]" } ], "info" : { "branch" : "branch1" }, "date" : ISODate("1970-01-01T00:00:00Z"), "money" : 5000 } -
如果被更新的字段值类型不一致，只要符合比较条件，也会被更新上去。
db.accounts.update({name: "kx"}, {$max: {money: "aaa"}}) WriteResult({ "nMatched" : 1, "nUpserted" : 0, "nModified" : 1 }) db.accounts.update({name: "kx"}, {$min: {money: null}}) WriteResult({ "nMatched" : 1, "nUpserted" : 0, "nModified" : 1 }) db.accounts.update({name: "kx"}, {$max: {money: 2000}}) WriteResult({ "nMatched" : 1, "nUpserted" : 0, "nModified" : 1 }) -
数组更新操作符$addToSet
-
向kx的账户文档中添加联系方式
db.accounts.find({name : "kx"}).pretty() { "_id" : ObjectId("5e154a6d297892ae4951650d"), "name" : "kx", "balance" : 6000, "contact" : [ [ "44444", "55555" ], "广东省", "china", { "primaryEmail" : "[email protected]", "secondaryEmail" : "[email protected]" } ], "info" : { "branch" : "branch1" }, "date" : ISODate("1970-01-01T00:00:00Z"), "money" : 2000 } > db.accounts.update({name: "kx"}, {$addToSet : { contact : "new ziduan" } }) WriteResult({ "nMatched" : 1, "nUpserted" : 0, "nModified" : 1 }) > db.accounts.find({name : "kx"}).pretty() { "_id" : ObjectId("5e154a6d297892ae4951650d"), "name" : "kx", "balance" : 6000, "contact" : [ [ "44444", "55555" ], "广东省", "china", { "primaryEmail" : "[email protected]", "secondaryEmail" : "[email protected]" }, "new ziduan" ], "info" : { "branch" : "branch1" }, "date" : ISODate("1970-01-01T00:00:00Z"), "money" : 2000 } -
当向数组中添加重复的值，是不会成功的。
db.accounts.update({name: "kx"}, {$addToSet : { contact : "new ziduan" } }) WriteResult({ "nMatched" : 1, "nUpserted" : 0, "nModified" : 0 }) -
向kx的账户文档中添加新的联系方式
db.accounts.find({name : "kx"}).pretty() { "_id" : ObjectId("5e154a6d297892ae4951650d"), "name" : "kx", "balance" : 6000, "contact" : [ [ "44444", "55555" ], "广东省", "china", { "primaryEmail" : "[email protected]", "secondaryEmail" : "[email protected]" }, "new ziduan" ], "info" : { "branch" : "branch1" }, "date" : ISODate("1970-01-01T00:00:00Z"), "money" : 2000 } //更新 > db.accounts.update({name: "kx"}, {$addToSet : { contact : {secondaryEmail: "[email protected]", "primaryEmail" : "[email protected]"} } }) WriteResult({ "nMatched" : 1, "nUpserted" : 0, "nModified" : 1 }) > db.accounts.find({name : "kx"}).pretty() { "_id" : ObjectId("5e154a6d297892ae4951650d"), "name" : "kx", "balance" : 6000, "contact" : [ [ "44444", "55555" ], "广东省", "china", { "primaryEmail" : "[email protected]", "secondaryEmail" : "[email protected]" }, "new ziduan", { "secondaryEmail" : "[email protected]", "primaryEmail" : "[email protected]" } ], "info" : { "branch" : "branch1" }, "date" : ISODate("1970-01-01T00:00:00Z"), "money" : 2000 } -
向kx的账户文档中添加多个联系方式
$addToSet会将数组插入被更新的数组字段中，成为内嵌数组。db.accounts.update({name: "kx"}, {$addToSet: {contact: ["contact1", "contact1"]}}) WriteResult({ "nMatched" : 1, "nUpserted" : 0, "nModified" : 1 }) > db.accounts.find({name : "kx"}).pretty() { "_id" : ObjectId("5e154a6d297892ae4951650d"), "name" : "kx", "balance" : 6000, "contact" : [ [ "44444", "55555" ], "广东省", "china", { "primaryEmail" : "[email protected]", "secondaryEmail" : "[email protected]" }, "new ziduan", { "secondaryEmail" : "[email protected]", "primaryEmail" : "[email protected]" }, [ "contact1", "contact1" ] ], "info" : { "branch" : "branch1" }, "date" : ISODate("1970-01-01T00:00:00Z"), "money" : 2000 } -
如果想要将多个元素直接添加到数组字段中，则需要使用$each操作符。
db.accounts.update({name: "kx"}, {$addToSet: {contact: {$each: ["contact1", "contact2"]} }}) WriteResult({ "nMatched" : 1, "nUpserted" : 0, "nModified" : 1 }) //一次性加入了两个元素 > db.accounts.find({name : "kx"}).pretty() { "_id" : ObjectId("5e154a6d297892ae4951650d"), "name" : "kx", "balance" : 6000, "contact" : [ [ "44444", "55555" ], "广东省", "china", { "primaryEmail" : "[email protected]", "secondaryEmail" : "[email protected]" }, "new ziduan", { "secondaryEmail" : "[email protected]", "primaryEmail" : "[email protected]" }, [ "contact1", "contact1" ], "contact1", "contact2" ], "info" : { "branch" : "branch1" }, "date" : ISODate("1970-01-01T00:00:00Z"), "money" : 2000 } -
数组中删除元素$pop
-
从kx的账户文档中删除最后一个联系方式
db.accounts.update({name: "kx"}, {$pop: {contact: 1}}) WriteResult({ "nMatched" : 1, "nUpserted" : 0, "nModified" : 1 }) //把contact数组中最后中一个元素删除了 > db.accounts.find({name : "kx"}).pretty() { "_id" : ObjectId("5e154a6d297892ae4951650d"), "name" : "kx", "balance" : 6000, "contact" : [ [ "44444", "55555" ], "广东省", "china", { "primaryEmail" : "[email protected]", "secondaryEmail" : "[email protected]" }, "new ziduan", { "secondaryEmail" : "[email protected]", "primaryEmail" : "[email protected]" }, [ "contact1", "contact1" ], "contact1" ], "info" : { "branch" : "branch1" }, "date" : ISODate("1970-01-01T00:00:00Z"), "money" : 2000 }
- 删除双重数组中的元素
db.accounts.update({name : "kx"}, {$pop : {"contact.6" : -1}})
WriteResult({ "nMatched" : 1, "nUpserted" : 0, "nModified" : 1 })
//删除了数组contact 中第7个元素中的第一个
> db.accounts.find({name : "kx"}).pretty()
{
"_id" : ObjectId("5e154a6d297892ae4951650d"),
"name" : "kx",
"balance" : 6000,
"contact" : [
[
"44444",
"55555"
],
"广东省",
"china",
{
"primaryEmail" : "[email protected]",
"secondaryEmail" : "[email protected]"
},
"new ziduan",
{
"secondaryEmail" : "[email protected]",
"primaryEmail" : "[email protected]"
},
[
"contact1"
],
"contact1"
],
"info" : {
"branch" : "branch1"
},
"date" : ISODate("1970-01-01T00:00:00Z"),
"money" : 2000
}-
删除掉数组中最后一个元素后，会留下空数组
注意：$pop操作符只能应用在数组字段上，应用在非数组上就会出错。db.accounts.update({name : "kx"}, {$pop : {"contact.6" : -1}}) WriteResult({ "nMatched" : 1, "nUpserted" : 0, "nModified" : 1 }) > db.accounts.find({name : "kx"}).pretty() { "_id" : ObjectId("5e154a6d297892ae4951650d"), "name" : "kx", "balance" : 6000, "contact" : [ [ "44444", "55555" ], "广东省", "china", { "primaryEmail" : "[email protected]", "secondaryEmail" : "[email protected]" }, "new ziduan", { "secondaryEmail" : "[email protected]", "primaryEmail" : "[email protected]" }, [ ], "contact1" ], "info" : { "branch" : "branch1" }, "date" : ISODate("1970-01-01T00:00:00Z"), "money" : 2000 } -
将ke的账户文档复制为lawrence的账户文档
db.accounts.find({name: "ke"}) { "_id" : ObjectId("5e133b15738962fb118b2554"), "name" : "ke", "balance" : 1800, "contact" : [ [ "1754684641", "195324664654" ], "陕西省", "China" ] } // 开始复制 > db.accounts.find({name: "ke"},{_id: 0}).forEach(function(doc){ var newDoc = doc; newDoc.name = "lawrence"; db.accounts.insert(newDoc); }) { "_id" : ObjectId("5e186ccb49c9a0cf0c039491"), "name" : "lawrence", "balance" : 1800, "contact" : [ [ "1754684641", "195324664654" ], "陕西省", "China" ] } -
$pull 删除数组中指定位置的元素
-
从lawrence的联系方式中，删去数组contact 中包含"664"字母的元素
db.accounts.find({name : "lawrence"}) { "_id" : ObjectId("5e186ccb49c9a0cf0c039491"), "name" : "lawrence", "balance" : 1800, "contact" : [ [ "1754684641", "195324664654" ], "陕西省", "China" ] } //删除了 china > db.accounts.update({name: "lawrence"}, {$pull : {"contact": {$regex : /in/}}}) WriteResult({ "nMatched" : 1, "nUpserted" : 0, "nModified" : 1 }) > db.accounts.find({name : "lawrence"}) { "_id" : ObjectId("5e186ccb49c9a0cf0c039491"), "name" : "lawrence", "balance" : 1800, "contact" : [ [ "1754684641", "195324664654" ], "陕西省" ] } -
从lawrence的联系方式中，删除联系电话号码包含“1754684641”的数组
{ "_id" : ObjectId("5e186ccb49c9a0cf0c039491"), "name" : "lawrence", "balance" : 1800, "contact" : [ [ "1754684641", "195324664654" ], "陕西省" ] } //删除了包含"1754684641"的数组 > db.accounts.update({name: "lawrence"}, {$pull : {"contact": {$elemMatch : {$eq: "1754684641"}}}}) WriteResult({ "nMatched" : 1, "nUpserted" : 0, "nModified" : 1 }) > db.accounts.find({name : "lawrence"}) { "_id" : ObjectId("5e186ccb49c9a0cf0c039491"), "name" : "lawrence", "balance" : 1800, "contact" : [ "陕西省" ] } -
$pull命令会山区包含指定的文档字段和字段值的文档元素，字段排列顺序不需要完全匹配
db.account.update({name: "小六"}, {$pull : {contact: {"aaa" : "ccom"}}}) WriteResult({ "nMatched" : 1, "nUpserted" : 0, "nModified" : 1 }) > db.account.find({name: "小六"}) { "_id" : ObjectId("5e1f14d742045a554e10c29c"), "name" : "小六", "balance" : 650, "contact" : [ [ 9800, 998888 ], "西安市", "陕西省" ] } -
$pullAll必须删除一个完整的数组
db.account.update({name: "小六"}, {$pullAll : {"contact" : [ [ 9800, 998888 ], "西安市", "陕西省", { "email" : "[email protected]", "secondemail" : "[email protected]" } ]}}) WriteResult({ "nMatched" : 1, "nUpserted" : 0, "nModified" : 1 }) > db.account.find({name: "小六"}) { "_id" : ObjectId("5e1f14d742045a554e10c29c"), "name" : "小六", "balance" : 650, "contact" : [ ] } -
向数组字段中添加元素$push
-
$push和$addToSet命令相似,但是$push命令的功能更强大
-
和$addToSet命令一样，如果$push命令中指定的数组字段不存在,这个字段会被添加到文档中
db.account.update({name:"lawrence"}, {$push: {newArray : "new element"}}) WriteResult({ "nMatched" : 1, "nUpserted" : 0, "nModified" : 1 }) > db.account.find({name: "lawrence"}) { "_id" : ObjectId("5e1f0df242045a554e10c294"), "name" : "lawrence", "balance" : 500, "newArray" : [ "new element" ] } -
$set、".$"更新数组中符合条件的第一个元素
db.account.find({name : "小九"}) { "_id" : ObjectId("5e1f1bb742045a554e10c29f"), "name" : "小九", "newArray" : [ "push41", "push2", "push3", "push4" ] } db.account.update({name: "小九", newArray: "push3"}, {$set : { "newArray.$": "updated"} }) WriteResult({ "nMatched" : 1, "nUpserted" : 0, "nModified" : 1 }) > db.account.find({name: "小九"}) { "_id" : ObjectId("5e1f1bb742045a554e10c29f"), "name" : "小九", "newArray" : [ "push41", "push2", "updated", "push4" ] } -
$set、".$[]"更新数组中所有元素
db.account.find({name: "小五"}) { "_id" : ObjectId("5e1f102142045a554e10c299"), "name" : "小五", "balance" : 650, "contact" : [ [ 558800, 7788 ], "西安市", "陕西省" ] } db.account.update({name: "小五"}, {$set: {"contact.0.$[]": "888888" }}) WriteResult({ "nMatched" : 1, "nUpserted" : 0, "nModified" : 1 }) db.account.find({name: "小五"}) { "_id" : ObjectId("5e1f102142045a554e10c299"), "name" : "小五", "balance" : 650, "contact" : [ [ "888888", "888888" ], "西安市", "陕西省" ] } -
update命令中使用的筛选条件只对应于一篇文档，及时刷选条件对应多篇文档，update命令仍然只会更新一篇文档
-
multi更新多个文档
db.account.update({},{$set:{balance: 650}}, {multi: true}) WriteResult({ "nMatched" : 16, "nUpserted" : 0, "nModified" : 9 }) -
MongoDB只能保证单个文档操作的原子性，不能保证多个文档操作的原子性。
-
更新多个文档的操作虽然在单一线程中执行，但是线程在执行过程中可能被挂起，以便其他线程也有机会对数据进行操作。
删除文档
- db.<collection>.remove(<query>, <options>)
<options>文档声明了一些删除操作的参数db.account.remove({balance: 800}) WriteResult({ "nRemoved" : 3 }) - 在默认情况下，remove会删除所有符合条件的文档
- 如果只想删除满足筛选条件的第一篇文档，可以使用justOne选项
- 删除一篇小于100的账户文档
db.account.remove({balance: 650},{justOne: true}) WriteResult({ "nRemoved" : 1 }) - 删除集合drop
- remove命令可以删除集合内的所有文档，但是不会删除集合
db.lianxi.find() { "_id" : ObjectId("5e20371bb79fceaf9ea4be8d"), "name" : "小一", "contact" : [ [ "00000", "777777" ], "西安", "陕西省" ], "balance" : 500 } //不会删除集合，只会删除数据 > db.lianxi.remove({balance: 500}) WriteResult({ "nRemoved" : 1 }) > show collections lianxi db.lianxi.find() { "_id" : ObjectId("5e203765b79fceaf9ea4be8e"), "name" : "小一", "contact" : [ [ "00000", "777777" ], "西安", "陕西省" ], "balance" : 500 } //会把集合删除掉 > db.lianxi.drop() true show collections//空的 - 如果集合中的文档数据很多，使用remove命令删除所有文档的效率不高，更加有效率的方法：使用drop命令删除集合，然后再创建空集合并创建索引。
- （未理解）对银行账户文档进行重新投影$project ()
db.account.insertMany([{name:{firstName:"alice", lastName: "wang"},balance:500},{name:{firstName:"bob", lastName: "yang"},balance:400}]) { "acknowledged" : true, "insertedIds" : [ ObjectId("5e204079b79fceaf9ea4be8f"), ObjectId("5e204079b79fceaf9ea4be90") ] } db.account.aggregate([{$project:{_id:0, balance:1, clientName: "$name.firstName"}}]) { "balance" : 500, "clientName" : "alice" } { "balance" : 400, "clientName" : "bob" }db.account.aggregate([{$project:{_id:0, balance:1, nameArray: ["$name.firstName", "$name.middleName", "$name.lastName"]}}]) { "balance" : 500, "nameArray" : [ "alice", null, "wang" ] } { "balance" : 400, "nameArray" : [ "bob", null, "yang" ] }
聚合管道
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(待理解)$project是一个很常用的聚合阶段，可以用来灵活的控制输出文档的格式，也可以用来剔除不相关的字段，已优化聚合管道操作的性能。
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对银行账户文档进行筛选$match
db.account.aggregate([{$match:{"name.firstName": "alice"}}]) { "_id" : ObjectId("5e204079b79fceaf9ea4be8f"), "name" : { "firstName" : "alice", "lastName" : "wang" }, "balance" : 500 } db.account.aggregate([{$match:{$or:[{balance: {$gt:390, $lt:410}}, {"name.lastName": "yang"}]}}]) { "_id" : ObjectId("5e204079b79fceaf9ea4be90"), "name" : { "firstName" : "bob", "lastName" : "yang" }, "balance" : 400 } db.account.aggregate([{$match:{$or:[{balance: {$gt:390, $lt:410}}, {"name.lastName": "yang"}]}}, {$project: { _id : 0}}]) { "name" : { "firstName" : "bob", "lastName" : "yang" }, "balance" : 400 } -
$limit和$skip
-
筛选第一篇银行账户文档
db.account.aggregate([{$limit:1}]) { "_id" : ObjectId("5e2035cab79fceaf9ea4be88"), "name" : "小柯", "contact" : [ "11702908819" ] } -
调过第一篇银行账户文档
db.account.aggregate([{$skip:1}]) { "_id" : ObjectId("5e203605b79fceaf9ea4be89"), "name" : "小一", "contact" : [ "11702908819", "西安", "陕西省" ] } { "_id" : ObjectId("5e203630b79fceaf9ea4be8a"), "name" : "小一", "contact" : [ [ "00000", "777777" ], "西安", "陕西省" ] } { "_id" : ObjectId("5e20366cb79fceaf9ea4be8b"), "name" : "小一", "contact" : [ [ "00000", "777777" ], "西安", "陕西省" ], "ke" : { "aa" : "bb", "cc" : "dd" } } { "_id" : ObjectId("5e203689b79fceaf9ea4be8c"), "name" : "小一", "contact" : [ [ "00000", "777777" ], "西安", "陕西省" ], "balance" : 500 } { "_id" : ObjectId("5e204079b79fceaf9ea4be8f"), "name" : { "firstName" : "alice", "lastName" : "wang" }, "balance" : 500 } { "_id" : ObjectId("5e204079b79fceaf9ea4be90"), "name" : { "firstName" : "bob", "lastName" : "yang" }, "balance" : 400 } -
将文档中的货币种类数组展开
db.account.find({"name.firstName": "alice"}) { "_id" : ObjectId("5e204079b79fceaf9ea4be8f"), "name" : { "firstName" : "alice", "lastName" : "wang" }, "balance" : 500, "currency" : [ "CNY", "USD" ], "array" : [ "one", "two" ] } //会把一条记录拆分成两条 db.account.aggregate([{$unwind:{path: "$currency"}}]) { "_id" : ObjectId("5e204079b79fceaf9ea4be8f"), "name" : { "firstName" : "alice", "lastName" : "wang" }, "balance" : 500, "currency" : "CNY", "array" : [ "one", "two" ] } { "_id" : ObjectId("5e204079b79fceaf9ea4be8f"), "name" : { "firstName" : "alice", "lastName" : "wang" }, "balance" : 500, "currency" : "USD", "array" : [ "one", "two" ] } -
展开数组时添加元素位置
> db.account.aggregate([{$unwind:{path:"$currency", includeArrayIndex: "ccyIndex"}}]) { "_id" : ObjectId("5e203605b79fceaf9ea4be89"), "name" : "小一", "contact" : [ "11702908819", "西安", "陕西省" ], "currency" : "RMB", "ccyIndex" : null } { "_id" : ObjectId("5e204079b79fceaf9ea4be8f"), "name" : { "firstName" : "alice", "lastName" : "wang" }, "balance" : 500, "currency" : "CNY", "array" : [ "one", "two" ], "ccyIndex" : NumberLong(0) } { "_id" : ObjectId("5e204079b79fceaf9ea4be8f"), "name" : { "firstName" : "alice", "lastName" : "wang" }, "balance" : 500, "currency" : "USD", "array" : [ "one", "two" ], "ccyIndex" : NumberLong(1) } { "_id" : ObjectId("5e204079b79fceaf9ea4be90"), "name" : { "firstName" : "bob", "lastName" : "yang" }, "balance" : 400, "currency" : "GBP", "ccyIndex" : null } -
展开数组时保留数组或不存在数组的文档
db.account.find() { "_id" : ObjectId("5e2035cab79fceaf9ea4be88"), "name" : "小柯", "contact" : [ "11702908819" ] } { "_id" : ObjectId("5e203605b79fceaf9ea4be89"), "name" : "小一", "contact" : [ "11702908819", "西安", "陕西省" ], "currency" : "RMB" } { "_id" : ObjectId("5e203630b79fceaf9ea4be8a"), "name" : "小一", "contact" : [ [ "00000", "777777" ], "西安", "陕西省" ] } { "_id" : ObjectId("5e20366cb79fceaf9ea4be8b"), "name" : "小一", "contact" : [ [ "00000", "777777" ], "西安", "陕西省" ], "ke" : { "aa" : "bb", "cc" : "dd" } } { "_id" : ObjectId("5e203689b79fceaf9ea4be8c"), "name" : "小一", "contact" : [ [ "00000", "777777" ], "西安", "陕西省" ], "balance" : 500 } { "_id" : ObjectId("5e204079b79fceaf9ea4be8f"), "name" : { "firstName" : "alice", "lastName" : "wang" }, "balance" : 500, "currency" : [ "CNY", "USD" ], "array" : [ "one", "two" ] } { "_id" : ObjectId("5e204079b79fceaf9ea4be90"), "name" : { "firstName" : "bob", "lastName" : "yang" }, "balance" : 400, "currency" : "GBP" } { "_id" : ObjectId("5e2053faf47293d1b9146730"), "name" : { "firstName" : "charlie", "lastName" : "gordon" }, "balance" : 100 } { "_id" : ObjectId("5e2053faf47293d1b9146731"), "name" : { "firstName" : "david", "lastName" : "wu" }, "balance" : 200, "currency" : [ ] } { "_id" : ObjectId("5e2053faf47293d1b9146732"), "name" : { "firstName" : "eddie", "lastName" : "kim" }, "balance" : 20, "currency" : null } > db.account.aggregate([{$unwind:{path:"$currency"}}]) { "_id" : ObjectId("5e203605b79fceaf9ea4be89"), "name" : "小一", "contact" : [ "11702908819", "西安", "陕西省" ], "currency" : "RMB" } { "_id" : ObjectId("5e204079b79fceaf9ea4be8f"), "name" : { "firstName" : "alice", "lastName" : "wang" }, "balance" : 500, "currency" : "CNY", "array" : [ "one", "two" ] } { "_id" : ObjectId("5e204079b79fceaf9ea4be8f"), "name" : { "firstName" : "alice", "lastName" : "wang" }, "balance" : 500, "currency" : "USD", "array" : [ "one", "two" ] } { "_id" : ObjectId("5e204079b79fceaf9ea4be90"), "name" : { "firstName" : "bob", "lastName" : "yang" }, "balance" : 400, "currency" : "GBP" } -
展开数组时保留空数组或不存在数组的文档
> db.account.aggregate([{$unwind:{path:"$currency", preserveNullAndEmptyArrays: true}}]) { "_id" : ObjectId("5e2035cab79fceaf9ea4be88"), "name" : "小柯", "contact" : [ "11702908819" ] } { "_id" : ObjectId("5e203605b79fceaf9ea4be89"), "name" : "小一", "contact" : [ "11702908819", "西安", "陕西省" ], "currency" : "RMB" } { "_id" : ObjectId("5e203630b79fceaf9ea4be8a"), "name" : "小一", "contact" : [ [ "00000", "777777" ], "西安", "陕西省" ] } { "_id" : ObjectId("5e20366cb79fceaf9ea4be8b"), "name" : "小一", "contact" : [ [ "00000", "777777" ], "西安", "陕西省" ], "ke" : { "aa" : "bb", "cc" : "dd" } } { "_id" : ObjectId("5e203689b79fceaf9ea4be8c"), "name" : "小一", "contact" : [ [ "00000", "777777" ], "西安", "陕西省" ], "balance" : 500 } { "_id" : ObjectId("5e204079b79fceaf9ea4be8f"), "name" : { "firstName" : "alice", "lastName" : "wang" }, "balance" : 500, "currency" : "CNY", "array" : [ "one", "two" ] } { "_id" : ObjectId("5e204079b79fceaf9ea4be8f"), "name" : { "firstName" : "alice", "lastName" : "wang" }, "balance" : 500, "currency" : "USD", "array" : [ "one", "two" ] } { "_id" : ObjectId("5e204079b79fceaf9ea4be90"), "name" : { "firstName" : "bob", "lastName" : "yang" }, "balance" : 400, "currency" : "GBP" } { "_id" : ObjectId("5e2053faf47293d1b9146730"), "name" : { "firstName" : "charlie", "lastName" : "gordon" }, "balance" : 100 } { "_id" : ObjectId("5e2053faf47293d1b9146731"), "name" : { "firstName" : "david", "lastName" : "wu" }, "balance" : 200 } { "_id" : ObjectId("5e2053faf47293d1b9146732"), "name" : { "firstName" : "eddie", "lastName" : "kim" }, "balance" : 20, "currency" : null } -
对银行账户文档进行排序
> db.account.aggregate([{$sort:{balance:1, "name.lastName": -1}}]) { "_id" : ObjectId("5e2035cab79fceaf9ea4be88"), "name" : "小柯", "contact" : [ "11702908819" ] } { "_id" : ObjectId("5e203605b79fceaf9ea4be89"), "name" : "小一", "contact" : [ "11702908819", "西安", "陕西省" ], "currency" : "RMB" } { "_id" : ObjectId("5e203630b79fceaf9ea4be8a"), "name" : "小一", "contact" : [ [ "00000", "777777" ], "西安", "陕西省" ] } { "_id" : ObjectId("5e20366cb79fceaf9ea4be8b"), "name" : "小一", "contact" : [ [ "00000", "777777" ], "西安", "陕西省" ], "ke" : { "aa" : "bb", "cc" : "dd" } } { "_id" : ObjectId("5e2053faf47293d1b9146732"), "name" : { "firstName" : "eddie", "lastName" : "kim" }, "balance" : 20, "currency" : null } { "_id" : ObjectId("5e2053faf47293d1b9146730"), "name" : { "firstName" : "charlie", "lastName" : "gordon" }, "balance" : 100 } { "_id" : ObjectId("5e2053faf47293d1b9146731"), "name" : { "firstName" : "david", "lastName" : "wu" }, "balance" : 200, "currency" : [ ] } { "_id" : ObjectId("5e204079b79fceaf9ea4be90"), "name" : { "firstName" : "bob", "lastName" : "yang" }, "balance" : 400, "currency" : "GBP" } { "_id" : ObjectId("5e204079b79fceaf9ea4be8f"), "name" : { "firstName" : "alice", "lastName" : "wang" }, "balance" : 500, "currency" : [ "CNY", "USD" ], "array" : [ "one", "two" ] } { "_id" : ObjectId("5e203689b79fceaf9ea4be8c"), "name" : "小一", "contact" : [ [ "00000", "777777" ], "西安", "陕西省" ], "balance" : 500 }
