张波的技术积累

产品表:{ _id: new ObjectId("4c4b1476238d3b4dd5003981"),slug:"wheel-barrow-9092",sku: "9092",name:"Extra Large Wheel Barrow",description: "Heavy duty wheelbarrow...",details: {weight: 47,weight_u

package com.mongodb;import java.net.UnknownHostException;import com.mongodb.util.JSON;public class Test1 { public static void main(String[] args) throws UnknownHostException { Mongo mongo

SqlMongodbSELECT * FROM usersDb.users.find()SELECT a,b FROM usersDb.users.find({},{a:1,b:1})SELECT * FROM users WHERE age=33Db.users.find({age:33}