Connect function:

/**
 * Connect to the database server
 */
function connect() {
	$con = mysql_connect('localhost', 'username', 'password') or die('Could not connect: ' . mysql_error());
	mysql_select_db('database_name') or die('Could not select the database: ' . mysql_error());
	return $con;
}

---

Disconnect function:

/**
 * Disconnect from the database server
 */
function disconnect($con) {
	mysql_close($con);
}

---

Generic Read Function:

function read() {
		$con =  connect();
		
		$query = "SELECT `field1`, `field2` FROM `table` WHERE `field3`='value' ORDER BY `field4` ASC/DESC LIMIT $start,$finish";
		$result = mysql_query($query) or die('Could not retrieve Fields: ' . mysql_error());

		while ($row = mysql_fetch_assoc($result))
			$foo += $row['field1'] * $row['field2'];
		
		disconnect($con);
}

---

Generic Write Function:

function write($value1, $value2) {
	$con = connect();
	
	$query = "UPDATE `table` SET `field1`='$value1', `field2`='$value2', WHERE `field`='$value' LIMIT $num"; //usually LIMIT 1
	mysql_query($query) or die('Could not update Table: ' . mysql_error());
	
	disconnect($con);
}

---

Generic Insert Function:

function insert($value1, $value2) {
	$con = connect();

	$query = "INSERT INTO `table` (`field1`, `field2`) VALUES ('$value1', '$value2')";
	mysql_query($query) or die('Could not insert Entry: ' . mysql_error());
	
	disconnect($con);
}

---

Generic Delete Function

function write($value) {
	$con = connect();
	
	$query = "DELETE FROM `table` WHERE `field`='value' LIMIT $num"; //usually LIMIT 1
	mysql_query($query) or die('Could not delete Entry: ' . mysql_error());
	
	disconnect($con);
}