Express : undefined await function

Question

I'm getting undefined after executing the ExecuteSQL function. The login function uses the ExecuteSQL function is used to check whether a user exists? I'm getting the following error while I'm running this file. async await.

[nodemon] restarting due to changes... >[nodemon] starting node DL.js >undefined >undefined >indicator1

  async function ExecuteSQL(strSQL) {
        try {
            const pool = await getConnection();
            if (pool) {
                const result = await pool.request()
                    .query(strSQL, async function (err, sqlResult) {
                        if (err) {
                            console.log(err);
                        }
                        else {
    //                        console.log(strSQL);
    //                        console.log(sqlResult);
                            return sqlResult;
                        }
                    });
            }
            else console.log(pool);
        } catch (err) {
            console.log(err);
        }
    };
    
    
    async function login(strUID) {
        const strSQL = `SELECT fUserPwd FROM tblUser WHERE fUserID ='${strUID}'`;
        try {
            const result = await ExecuteSQL(strSQL).then(function (data) {
                console.log(data);
                return data
               });
               
               console.log(result);
            console.log('indicator1')
        } catch (err) {
            console.log(err);
        }
    
    };
    
    login('ADMIN');

Answer 1

You are not returning anything from ExecuteSQL. Furthermore, you should not mix async/await with callbacks. And you should not mix async/await with .then() Decide which one you like better and stick with your decision.

You can just do

async function ExecuteSQL(strSQL) {
    try {
        const pool = await getConnection();
        //you don't need to check for the pool, because getConnection() will throw if there is an error 
        const result = await pool.request().query(strSQL);
        return result;
    } catch (err) {
        console.log(err);
    }
};


async function login(strUID) {
    const strSQL = `SELECT fUserPwd FROM tblUser WHERE fUserID ='${strUID}'`;
    try {
        const result = await ExecuteSQL(strSQL);
        console.log(result);
        return result;
    } catch (err) {
        console.log(err);
    }

};

And you should NEVER construct your queries with string concatenation or string templates because that's very error prone and insecure. See the mssql manual on how to create parameterized queries.