const util = require('util');

const mysql = require('mysql');

const connection = mysql.createConnection({

host: 'localhost',

user: 'hyfuser',

password: 'hyfpassword',

database: 'class17',

});

// Promisify the bind function of query function of connection object

// Pass connection object (because bind expects "this")

// Afterwards execQuery will work as a function that returns a promise but

// we don't have to call "then" over that promise

const execQuery = util.promisify(connection.query.bind(connection));

async function seedDatabase() {

const CREATE_STUDENTS_TABLE = `

CREATE TABLE IF NOT EXISTS students (

student_number INT,

student_name VARCHAR(50),

date_of_birth DATE,

grade FLOAT,

gender ENUM('m', 'f')

);`;

const CREATE_TEACHERS_TABLE = `

CREATE TABLE IF NOT EXISTS teachers (

teacher_number INT,

teacher_name VARCHAR(50),

date_of_birth DATE,

subject TEXT,

gender ENUM('m', 'f')

);`;

const students = [

{

student_number: 4444,

student_name: 'Benno',

date_of_birth: '1995-04-26',

grade: 8.3,

gender: 'm',

},

{

student_number: 3333,

student_name: 'Henriata',

date_of_birth: '1998-05-12',

grade: 8.5,

gender: 'm',

},

];

connection.connect();

try {

// call the function that returns promise

await execQuery(CREATE_STUDENTS_TABLE);

await execQuery(CREATE_TEACHERS_TABLE);

students.forEach(async student => {

await execQuery('INSERT INTO students SET ?', student);

});

} catch (error) {

console.error(error);

}

connection.end();

}

seedDatabase();