Jassif Team Institution

let mysql = require('mysql');

let con = mysql.createConnection({
  host: "localhost",
  user: "yourusername",
  password: "yourpassword",
  database: "mydb"
});

con.connect(function(err) {
  if (err) throw err;
  console.log("Connected!");
  let sql = "CREATE TABLE customers (name VARCHAR(255), address VARCHAR(255))";
  con.query(sql, function (err, result) {
    if (err) throw err;
    console.log("Table created");
  });
});

C:\Users\Your Name>node demo_create_table.js

Connected!
Table created

let mysql = require('mysql');

let con = mysql.createConnection({
  host: "localhost",
  user: "yourusername",
  password: "yourpassword",
  database: "mydb"
});

con.connect(function(err) {
  if (err) throw err;
  console.log("Connected!");
  let sql = "CREATE TABLE customers (id INT AUTO_INCREMENT PRIMARY KEY, name VARCHAR(255), address VARCHAR(255))";
  con.query(sql, function (err, result) {
    if (err) throw err;
    console.log("Table created");
  });
});

let mysql = require('mysql');

let con = mysql.createConnection({
  host: "localhost",
  user: "yourusername",
  password: "yourpassword",
  database: "mydb"
});

con.connect(function(err) {
  if (err) throw err;
  console.log("Connected!");
  let sql = "ALTER TABLE customers ADD COLUMN id INT AUTO_INCREMENT PRIMARY KEY";
  con.query(sql, function (err, result) {
    if (err) throw err;
    console.log("Table altered");
  });
});

CREATE TABLE users (
  id INT AUTO_INCREMENT PRIMARY KEY,
  username VARCHAR(50) NOT NULL UNIQUE,
  email VARCHAR(100) NOT NULL UNIQUE,
  age INT CHECK (age >= 18),
  created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP
);

con.query("SHOW TABLES", function (err, result) {
  if (err) throw err;
  console.log("Tables:");
  result.forEach(row => {
    console.log(row.Tables_in_mydb);
  });
});

con.query("DESCRIBE customers", function (err, result) {
  if (err) throw err;
  console.log("Table structure:");
  result.forEach(row => {
    console.log(`${row.Field} - ${row.Type} - ${row.Key}`);
  });
});

con.query("DROP TABLE customers", function (err, result) {
  if (err) throw err;
  console.log("Table deleted");
});

const mysql = require('mysql');

// Create connection
const con = mysql.createConnection({
  host: "localhost",
  user: "root",
  password: "password",
  database: "company_db"
});

// Connect to MySQL
con.connect((err) => {
  if (err) {
    console.error('Error connecting to MySQL:', err.message);
    return;
  }
  
  console.log('Connected to MySQL database');
  
  // Create table if not exists
  const createTableSQL = `
    CREATE TABLE IF NOT EXISTS employees (
      id INT AUTO_INCREMENT PRIMARY KEY,
      first_name VARCHAR(50) NOT NULL,
      last_name VARCHAR(50) NOT NULL,
      email VARCHAR(100) UNIQUE NOT NULL,
      salary DECIMAL(10,2) DEFAULT 0.00,
      hire_date DATE,
      department VARCHAR(50),
      created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP
    )
  `;
  
  con.query(createTableSQL, (err, result) => {
    if (err) {
      console.error('Error creating table:', err.message);
      con.end();
      return;
    }
    
    console.log('Employees table created or already exists');
    
    // Show table structure
    con.query("DESCRIBE employees", (err, result) => {
      if (err) {
        console.error('Error describing table:', err.message);
        con.end();
        return;
      }
      
      console.log('\nTable structure:');
      console.log('Field\t\tType\t\tNull\tKey\tDefault');
      console.log('---------------------------------------------------');
      result.forEach(row => {
        console.log(`${row.Field}\t${row.Type}\t${row.Null}\t${row.Key}\t${row.Default}`);
      });
      
      // Close connection
      con.end((err) => {
        if (err) {
          console.error('Error closing connection:', err.message);
          return;
        }
        console.log('\nConnection closed');
      });
    });
  });
});