MongoDB v4.0 命令
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操作系统库
#操作管理员库
use admin
#鉴权
db.auth("root","admin");
#用户查看(格式美化)
db.system.users.find().pretty();
#新增用户
db.createUser({
user: 'root1',
pwd: 'admin1',
roles: [ { role: "dbOwner", db: "yapi" }]
});
#更新用户信息/密码/权限
db.updateUser("root1",{
pwd: "admin2",
roles:
[{
role: "root",
db: "admin"
},{
role: "userAdminAnyDatabase",
db: "admin"
},{
role: "readWriteAnyDatabase",
db: "admin"
},{
role: "dbAdminAnyDatabase",
db: "admin"
}]})
#删除数据库所属用户
db.dropUser("root1");操作自定义库
#操作自定义库
use persionalDB
#鉴权
db.auth("user","pwd");
#创建数据库所属用户
db.createUser({
user: 'username1',
pwd: 'password1',
roles: [ { role: "dbOwner", db: "yapi" }]
});
#更新用户信息/密码/权限
db.updateUser("username1",{
pwd: "NEW pass",
roles:
[{
role: "root",
db: "admin"
},{
role: "userAdminAnyDatabase",
db: "admin"
},{
role: "readWriteAnyDatabase",
db: "admin"
},{
role: "dbAdminAnyDatabase",
db: "admin"
}]});
#删除数据库所属用户
db.dropUser("username1");1.0.0 基础操作 [collection]= 所查集合名
use [db_name];
db.[collection].insert({[title]:'[value]'});
eg:
db.hellocollction.insert({name:'hello'});
# 单个插入
db.inventory.insertOne(
{ item: "canvas",
qty: 100,
tags: ["cotton"],
size: {
h: 28,
w: 35.5,
uom: "cm"
}
}
)
# 批量插入
db.inventory.insertMany([
{ item: "journal", qty: 25, tags: ["blank", "red"], size: { h: 14, w: 21, uom: "cm" } },
{ item: "mat", qty: 85, tags: ["gray"], size: { h: 27.9, w: 35.5, uom: "cm" } },
{ item: "mousepad", qty: 25, tags: ["gel", "blue"], size: { h: 19, w: 22.85, uom: "cm" } }
])1.1 ============>增<============
- db.[collection].insertOne()/insertMany()
1.2 ============>查<============
- db.[[collection]].find()
1.3 ============>改<============
- db.[collection].updateOne()/updateMany()/replaceOne()
1.4 ============>删<============
- db.collection.deleteOne()/deleteMany()
2.0 高级: 联表查询 Join
初始数据
db.product.insert({"_id":1,"productname":"商品1","price":15});
db.product.insert({"_id":2,"productname":"商品2","price":36});
db.order.insert({"_id":1,"pid":1,"ordername":"订单1","uid":1});
db.order.insert({"_id":2,"pid":2,"ordername":"订单2","uid":2});
db.order.insert({"_id":3,"pid":2,"ordername":"订单3","uid":2});
db.order.insert({"_id":4,"pid":1,"ordername":"订单4","uid":1});
db.user.insert({"_id":1,"username":1});
db.user.insert({"_id":2,"username":2});
db.product.find();
db.order.find();
db.user.find();2.1
$lookup两表关联join
db.product.aggregate([
{
$lookup:
{
from: "order",
localField: "_id",
foreignField: "pid",
as: "inventory_docs"
}
}
]);
#结果:
{
"_id" : 1.0,
"productname" : "商品1",
"price" : 15.0,
"inventory_docs" : [
{
"_id" : 1.0,
"pid" : 1.0,
"ordername" : "订单1"
},
{
"_id" : 4.0,
"pid" : 1.0,
"ordername" : "订单4"
}
]
}lookup 就是使用 aggregate 的 $lookup 属性，$lookup 操作需要一个四个参数的对象：
- localField：在输入文档中的查找字段
- from：需要连接的集合
- foreignField：需要在from集合中查找的字段
- as：输出的字段名字
2.2 $lookup 三表关联join
db.order.aggregate([
{
"lookup": {
"from": "product",
"localField": "pid",
"foreignField": "_id",
"as": "inventory_docs"
}
},{
"lookup": {
"from": "user",
"localField": "uid",
"foreignField": "_id",
"as": "user_docs"
}
}
]);