nodeJS-MySql connection :

//inserting data into mysql database
const mysql=require('mysql')
const con=mysql.createConnection({
    host:'localhost',
    database:'compuhelp',
    user:'root',
    password:'Ghelp@123'
})
//following code to make connection to the database
con.connect()
console.log("Connected")
const myquery=`insert into student values(?,?,?)` //concept of prepared query
const q_param=['Aruhi',190,444444] //data of prepared query
con.query(myquery,q_param,function(err,result){
    if(err)
    {
        console.error('Some thing went wrong ')
    }
    else
    {
       // console.log(`The value of Result is ${result}`)
        console.log(`Data saved to database`)
    }

})

//following code to close the connection
con.end(function(err){
    if(err)
    {
        console.log("could not close connection")
    }
    else
    {
        console.log("Connection closed Successfully")
    }
})

//program to use mysql database for select data
const mysql=require('mysql')
con=mysql.createConnection({
    host:'localhost',
    database:'compuhelp',
    user:'root',
    password:'Ghelp@123'
})
msg=con.connect();
console.log(msg)
con.query('select * from student where fee>=?','30000',function(err,result){
    if(err)
    {
        console.error('something went wrong ' + err.message())
        return
    }
    console.log(result.length)
    console.log(`Name     Rollno      Fee`);
    for(row=0;row<result.length;row++)
    {
        console.log(`${result[row].name}    ${result[row].rollno}    ${result[row].fee} `)
    }
    console.log(result[0].name)
})
con.end(function(err){
    if(err)
    {
        console.log("Error closing connnection");
    }
    else
    {
        console.log('connection closed successfully');
    }
})