Mongodb 常见操作：查询，排序，查看索引，创建索引等

//insert
db.books.insert(
[
{ _id: 12, item: "pencil1", qty: 51, type: "no.1" },
{ _id: 21, item: "pencil1", qty: 52, type: "no.2" },
{ _id: 31, item: "pencil1", qty: 53, type: "no.3" },
]
)

db.books.insert([
{ 3 "title" : "book-51", 4 "type" : "technology", 5 "favCount" : 11, 6 "tag":[],
"author" : {
"name" : "fox",
"age" : 28
}
},{
"title" : "book-52",
"type" : "technology",
"favCount" : 15,
"author" : {
"name" : "fox",
"age" :
}
},{
"title" : "book-53",
"type" : "technology",
"tag" : [
"nosql",
"document"
],
"favCount" : 20,
"author" : {
"name" : "fox",
"age" : 28
}
}])

//$project 投影别名 聚合操作
db.books.find()
db.books.aggregate([{$project:{name:"$item",_id:0,type2:1}}])

//$group
db.books.aggregate([
{$group:{_id:"$item",total:{$sum: 1}}},
{$sort:{total: -1}}
])

//$match
db.books.aggregate([{$match:{"item":"pencil1"}}])

//$count
db.books.aggregate([
{$match:{type:"pencil1"}},
{$count: "qty"}])

//$ join
db.customer.aggregate([
{$lookup:{
from: "order",
localField: "customerCode",
foreignField: "customerCode",
as: "customerOrder"
}
}])

db.order.aggregate([
{$lookup:{
from: "customer",
localField: "customerCode",
foreignField: "customerCode",
as: "customer"
}
},
{$lookup:{
from: "orderItem",
localField: "orderId",
foreignField: "orderId",
as: "orderItem"
}
}
])

db.customer.insert({customerCode:1,name:"customer1",phone:"13112345678",address:"test1"
})

db.customer.insert({customerCode:2,name:"customer2",phone:"13112345679",address:"test2"
})
db.order.insert({orderId:1,orderCode:"order001",customerCode:1,price:200})
db.order.insert({orderId:2,orderCode:"order002",customerCode:2,price:400})
db.orderItem.insert({itemId:1,productName:"apples",qutity:2,orderId:1})
db.orderItem.insert({itemId:2,productName:"oranges",qutity:2,orderId:1})
db.orderItem.insert({itemId:3,productName:"mangoes",qutity:2,orderId:1})
db.orderItem.insert({itemId:4,productName:"apples",qutity:2,orderId:2})
db.orderItem.insert({itemId:5,productName:"oranges",qutity:2,orderId:2})
db.orderItem.insert({itemId:6,productName:"mangoes",qutity:2,orderId:2})

$sort
db.books.find().sort({qty:-1})
db.books.find().sort({qty:-1}).explain()

$使用mongoimport工具导入数据
mongoimport -h 192.168.65.1 -d test -u user -p pwd --authenticationDatabase=admin -c
zips --file D:\ProgramData\mongodb\import\zips.json

db.books.aggregate([{$match:{item:"pencil1"}}]).explain()
db.books.find({$match:{item:"pencil1"}}).explain()

$createIndex()
db.books.createIndex({item:1})
db.books.find({item:"pencil1"}).explain()

db.books.createIndex({type:1,item:1})
db.books.find({qty:{$gt:51}})