Nodejs with express jumps after 1 function is called directly to callback

i have a sample function in which i want to trigger 3 sql queries in one express post request

function getRelatedSalespersonByCardcode(req, res) {
    var reqJson = JSON.parse(req.body.json);
    var count = Object.keys(reqJson.cardcode).length;

    var tmpResult1, tmpResult2, tmpResult3 = [];


    var q = sql.open(connstr, function (err) {
        if (err) {
            console.log(err);
            return;
        }
        for (var i = 0; i < count; i++) {
            q.queryRaw("SELECT Division, Salesperson FROM SomeDB.dbo.MS2_Rel_BusinessPartnerSalesperson WHERE CardCode = " + reqJson.cardcode[i], function (e, results) {
                if (e) {
                    console.log(e);
                    return;
                }
                tmpResult1.push(results);
            });

            q.queryRaw("SELECT SlpCode, SlpName, Memo, Commission, GroupCode, UserSign, Active, U_wpABIS, U_sweDW," +
                " U_sweATT, U_sweDIV, U_sweEMPLOYEE, U_sweRETAILER FROM SomeDB.dbo.OSLP WHERE U_sweId = " + tmpResult1[1], function (e, results) {
                if (e) {
                    console.log(e);
                    return;
                }
                tmpResult2.push(results);
            });

            q.queryRaw("SELECT Code, Name, U_sweSALES FROM SomeDB.dbo.[@SWEDIV] WHERE Code = " + tmpResult3[0], function (e, results) {
                if (e) {
                    console.log(e);
                    return;
                }
                tmpResult3.push(results);
            });
        }
    });

    res.send(200, tmpResult2);

}

Anyway after 1 function is called inside my req, res function the callback is triggert.. so it jumps directly to the res.send(...) line.

i've played a bit around and it seems that this is how express works.

after a bit of googleing around i found out that i have to use the async lib.

i'd like to ask why express is working like this and if anybody maybe have a better solution than the async approach. i simply need a way to realize my scenario.

This is no issue of express and no issue at all. This is like node.js async programming is working. Let's examine what's happening in your code:

var tmpResult2;

// 1. async open sql connection
var q = sql.open(connstr, function (err) {
    // 3. query sql connection
});

// 2. render result
res.send(200, tmpResult2);
  1. SQL connection is opened asynchronously.
  2. Express render is called.
  3. SQL queries are executed.

As a consequence this code piece sends data to the client before the data was fetched. So the most simple solution is to invoke res.send inside of the callback like this:

var tmpResult2;

// 1. async open sql connection
var q = sql.open(connstr, function (err) {
  // 2. render result
  res.send(200, tmpResult2);
});

You can use the wonderful async module to deal with the queries (Take a look at the async waterfall function).