How to wait to send the response of data after the forach loop is over

js
I just create a 2 function to send the response var = y but unfortunately res.end() work before then my y++ works..

This code work well with for loop without mine query
but when i used a query it working stop and it gives res like below.
Before promise call.
Loop completed.
Promise resolved: 0
Next step.
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  //1. Create a new function that returns a promise
function firstFunction() {
    return new Promise((resolve, reject) => {
        let y = 0
        con.connect(function (err) {
            if (err) throw err;
            con.query("SELECT * FROM wp_posts WHERE `post_type` = 'post'", async function (err, result, fields) {
                if (err) throw err;
                result.forEach(element => {
                    console.log(element['ID']);
                    y++;
                });
                // get the results from post table
            });
        });
        // for (i = 0; i < 100; i++) {
        //     y++
        // }
        console.log('Loop completed.')
        resolve(y)
    })
}

//2. Create an async function
async function secondFunction() {
    console.log('Before promise call.')
    //3. Await for the first function to complete
    const result = await firstFunction()
    console.log('Promise resolved: ' + result)
    console.log('Next step.')
    res.end();
};

secondFunction()

>Solution :

How about this…

//1. Create a new function that returns a promise
function firstFunction() {
    return new Promise((resolve, reject) => {
        let y = 0
        con.connect(function (err) {
            if (err) throw err;
            con.query("SELECT * FROM wp_posts WHERE `post_type` = 'post'", async function (err, result, fields) {
                if (err) throw err;
                result.forEach(element => {
                    console.log(element['ID']);
                    y++;
                });
                // get the results from post table
                console.log('Loop completed.')
                resolve(y); // <---- Resolve the promise here
            });
        });
        // for (i = 0; i < 100; i++) {
        //     y++
        // }
        // console.log('Loop completed.')
        // resolve(y) // <--- Moving this inside con.query callback
    })
}

//2. Create an async function
async function secondFunction() {
    console.log('Before promise call.')
    //3. Await for the first function to complete
    const result = await firstFunction()
    console.log('Promise resolved: ' + result)
    console.log('Next step.')
    res.end();
};

secondFunction()