如何在ExpressJS中将Javascript变量保存到Mysql数据库中

Question

Please i am very new to node js and expressjs framework. I am developing a web Application and i am stuck. I have setup all my database requirements and all is working just fine , now i want to save some data into the database and i have the data store in a variable, but unfortunately the data stored in the variable(MyID) is not saved. This is my code

var= MyID

app.post("/addContact", function(req, res){

    var postData = {
       // MyID: req.body.txtemplyeeID************Get employee ID as a foreign Key and Insert it,
        EmployeeID:req.body.txtemployeeID,
        FatherName:req.body.txtfathersName,
        MotherName:req.body.txtMothersName,
        NameOfSpouse:req.body.txtSpouseName,
        SpouseAddress:req.body.txtSpouseAddress,
        ParentsAddress:req.body.txtParentsAddress,
        EmployeeAddress:req.body.txtEmployeeAddress

    };
    connection.connect();
    connection.query('SELECT MyID from employees where EmployeeID='+"'"+ postData.EmployeeID +"'" +'', function(err, rows, fields) {

        if (err) throw err;

        for (var i in rows)
        {
            var results = rows[i];
            MyID=results.MyID;
            console.log(MyID);

        }

    })

        connection.query('INSERT INTO EmployeeContacts(MyID,FatherName,MotherName,NameOfSpouse,SpouseAddress,ParentsAddress,EmployeeAddress) VALUES ('+"'"+ MyID +"'"+','+"'"+ postData.FatherName +"'" +','+"'"+ postData.MotherName +"'" +','+"'"+ postData.NameOfSpouse +"'" +','+"'"+ postData.SpouseAddress +"'" +','+"'"+ postData.ParentsAddress +"'" +','+"'"+ postData.EmployeeAddress +"'" +');',
        function(err,results){
            if(err)console.log(err);
            else
            console.log("Success");
            connection.end() ;
            res.redirect("/addContact");

        });

});

}

Answer 1

Since you have a properly formed object, you should use :

connection.query('INSERT INTO EmployeeContracts SET ?', postData, function(err, results) {
  if (err) {
    console.error(err);
  } else {
    res.redirect('/addContract');
});

This is safer and cleaner. Also, I don't think you must end the connection explicitly after the query is treated.

And to avoid your second query to be executed before the first ends, just split those in two function and pass the MyId as a callback for the insertion with the object you created with the post data.