mysql - Node mysql顺序查询执行

Question

我正在尝试获取一些结果并根据这些结果进行进一步处理，但我无法继续按顺序处理它，

var sql = query1;

    con.query(sql, function (err, results) {
      if (err) throw err;
     //  ids => 5,2,3,4
      for (i = 0; i < results.length; i++) {

        target_user = results[i].ID

        var sql = "DELETE QUERY";

        con.query(sql, function (err) {
          if (err) throw err;
          console.log(target_user)

          var sql = "INSERT QUERY";
          console.log(sql)
          con.query(sql, function (err) {
            if (err) throw err;

          })
        })


      }
    })

上面的代码是异步运行的，我期望的是这样一个循环的输出

// "DELETE QUERY";
//5
// "INSERT QUERY";
// "DELETE QUERY";
//2
// "INSERT QUERY";

等等..

但我得到的是

// "DELETE QUERY";
//5
// "DELETE QUERY";
//5 //not fetching the next array val
// "INSERT QUERY";
// "INSERT QUERY";

非常感谢任何帮助。

---

编辑

从答案中我更新了这样的代码

现在代码是这样的

 aysnc.forEach(results, function(elem, callback){
target_user = elem.id
   console.log('out')
                    console.log(target_user)
                    con.query(sql, function (err) {
                      if (err) throw err;
                      console.log('in')
                    console.log(target_user)
})
})

奇怪的事情发生了，输出是

out
5
in
5
out
2
in
5 //when it is supposed to be 2

Answer 1

您仍然可以以不同的方式使用 npm 模块 async

const mysql = require('mysql');
const async = require('aynsc');

var db; //database variable
async.series([
  //creates DB connection and connects
  function(callback){
    db = mysql.createConnection(DB_INFO); //DB_INFO is an Object with information on the BD to be connected

    db.connect(function(err){
      if (err) {
        console.error('error connecting: ' + err.stack);
        return;
      }
      callback(); //goes to the next function
    }); 
  },

  //performs the Query 1
  function(callback){
    db.query('QUERY1', function(){
      callback(); //goes to the next function
    });    
  },

  //performs the Query 2 only after Query 1 is finished
  function(callback){
    db.query('QUERY2', function(){
      db.end(); //closes connection
      callback();
    });    
  }
]);