Configuring PHP to work with MySQL:
Now that both PHP and MySQL are installed, we have to configure them to work together.

1. Open up your php.ini file (C:/WINDOWS/php.ini) and find the line:

;extension=php_mysql.dll

To enable the MySQL extension, delete the semi-colon at the beginning of that line.

2. Next we must add the PHP directory to the Windows PATH. To do this, click: Start > My Computer > Properties > Advanced > Environment Variables. Under the second list (System Variables), there will be a variable called "Path". Select it and click "Edit". Add ";C:\php" to the very end of the string and click "OK".

3. Restart your computer for the changes to take effect.

4. Create a new file in your "htdocs" directory called "mysql_test.php".

5. Copy the following code into "mysql_test.php" and click save. (Make sure to replace the MYSQL_PASS constant with the MySQL Password you specified during the MySQL installation).

Code:

<?php

# Define MySQL Settings
define("MYSQL_HOST", "localhost");
define("MYSQL_USER", "root");
define("MYSQL_PASS", "password");
define("MYSQL_DB", "test");

$conn = mysql_connect("".MYSQL_HOST."", "".MYSQL_USER."", "".MYSQL_PASS."") or die(mysql_error());
mysql_select_db("".MYSQL_DB."",$conn) or die(mysql_error());

$sql = "SELECT * FROM test";
$res = mysql_query($sql);

while ($field = mysql_fetch_array($res))
{
$id = $field['id'];
$name = $field['name'];

echo 'ID: ' . $field['id'] . '<br />';
echo 'Name: ' . $field['name'] . '<br /><br />';
}

?>

6. Open up Internet Explorer and type in "http://localhost/mysql_test.php". If the "mysql_test.php" page returns something similiar to:

ID: 1
Name: John 

'; echo 'Name: ' . $field['name'] . '

'; } ?>

Bạn kiểm tra lại :

1. Vào phpmyadmin để xem và tạo database chưa ? Đặt tên Database có đúng không ?
2. Kiểm tra Username và Password vào database có đúng không ?  

Mình nghĩ bạn cài đặt toàn bộ phần mềm WAMP luôn đi cho dễ làm việc .