Connecting to MySQL, Querying Data, and Displaying Results with PHP

★ Type localhost in your web browser
★ Click phpMyAdmin, you will see a website that can deal with database.
★ Here is one tuotrial to create databases, tables, and reset username and password in phpMyAdmin on XAMPP.
★ Here is another

PHP + MySQL

In this section, we will learn how to connect to a MySQL database, run SQL queries, and display the results using PHP.

★ Here is one example to open a MySQL database
★ In XAMPP, the servername is localhost , username is root and password is empty by default.

	<!DOCTYPE html>
	<html>
	<head>
		<title></title>
	</head>
	<body>
	<?php
	$servername = "localhost";
	$username = "root";
	$password = "";
	
	// Connect to MySQL Database Server Using mysqli
	// Object Oriented way
	$conn = new mysqli($servername, $username, $password);
	
	// Check connection
	if ($conn->connect_error) {
		       //Print a message and terminate the current script
			die("Connection failed: " . $conn->connect_error);
	}
	echo "Connected successfully";
	
	$conn->close(); //disconnect from the MySQL database
	?>
	</body>
	</html>

★ Another Example:

	<?php
	$servername = "localhost";
	$username = "root";
	$password = "";
	
	// Create connection
	$conn = new mysqli($servername, $username, $password);
	// Check connection
	if ($conn->connect_error) {
	    die("Connection failed: " . $conn->connect_error);
	}
	
	echo "Connected successfully";
		
	// Create database
	$sql = "CREATE DATABASE CSCI4410";
	if ($conn->query($sql) === TRUE) {
	    echo "Database created successfully";
	} else {
	    echo "Error creating database: " . $conn->error;
	}
	
	$conn->close();
	?>

★ Create Database in phpmyadmin

tutorial

★ Usually, we connect to some MySQL database:

	<?php
	$servername = "localhost";
	$username = "root";
	$password = "";
	$database = "CSCI4410"; //you need to create this database in PHPMyAdmin
	// Create connection
	$conn = new mysqli($servername, $username, $password, $database);
	// Check connection
	if ($conn->connect_error) {
	    die("Connection failed: " . $conn->connect_error);
	}

	echo "Connected successfully";
	
	// write the SQL query
	$sql = "SELECT * FROM Persons"; //select all the columns from database table Persons
	//Perform query on a database
	$result = mysqli_query($conn, $sql); //fetch the resulting rows as an associated array

	$sql2 = "SELECT COLUMN_NAME
	FROM INFORMATION_SCHEMA.COLUMNS
	WHERE TABLE_SCHEMA ='CSCI4410' AND TABLE_NAME = 'Persons'"; // select all column names from table Persons
	$columns = mysqli_query($conn,$sql2); 
	
	echo "<br>";
	//Use table to display the database table
	echo "<table border='1'>"; // table start

	// table heading
	echo "<tr>";
	while($row = mysqli_fetch_assoc($columns))
	{
		foreach($row as $value)
			echo "<th>" . $value . "</th>";
	}
	echo "<tr>";

	// table rows
	while ($row = mysqli_fetch_assoc($result)) //Get row from database table
	{ 
			echo "<tr>";
			foreach ($row as $value) { // get the value for each row
					echo "<td>" . $value . "</td>"; 
			}
			echo "</tr>";
	}
	echo "</table>"; // table end

	$conn->close();
	?>

persons.sql