var mysql = require("mysql"); var conn = mysql.createConnection({ host:"localhost", port:"3306", user:"root", password:"root", database:"mydb" }); conn.connect(); console.log('query pre'); //异步执行 conn.query("select * from user_info",function(err,rows,fields){ if(err)console.log("查询失败%s",err); for(var i in rows){ console.log(rows[i]); } }); console.log('insert pre'); //异步执行 //同步执行 ? conn.query("INSERT INTO user_info (user_name, password,user_Number) VALUES('hunter2','123456','999')",function(err,res){ if(!err)console.log("添加成功%s",res.insertId); sleep(4000);// 模拟阻塞4s,等待的过程中,后面的修改、查询都不会执行。 console.log("新增执行完成"); }); console.log('update pre'); //异步执行 //同步执行 ? conn.query("UPDATE `user_info` SET `password` = '88888', `user_Number` = '888' WHERE `user_name` = 'hunter2'",function(err,res){ if(!err)console.log("修改成功%s",res.changedRows); }); console.log('query pre2'); //异步执行 //同步执行 ? conn.query("select * from user_info",function(err,rows,fields){ if(err)console.log("查询失败%s",err); for(var i in rows){ console.log(rows[i]); } }); function sleep(ms){ var startTime = new Date().getTime(); while(new Date().getTime() < startTime+ms); }