Hi Neeraj,
Its not like that we are going to use a file system to handing our data. We'll use MySQL to hold it.
If there is no tutorial related to PHP and Mysql database connectivity. See below code to understand it.
Opening a connection to MySQL database from PHP is easy. Just use the mysql_connect() function like this
<?php
$dbhost = 'localhost'; //since running on local server
$dbuser = 'root';
$dbpass = ''; //by default there is no password
$conn = mysql_connect($dbhost, $dbuser, $dbpass) or die ('Error connecting to mysql');
$dbname = 'petstore';
mysql_select_db($dbname);
?>
$dbhost is the name of MySQL server. When your webserver is on the same machine with the MySQL server you can use localhost or 127.0.0.1 as the value of $dbhost. The $dbuser and $dbpass are valid MySQL user name and password. For adding a user to MySQL visit this page : MySQL Tutorial
Don't forget to select a database using mysql_select_db() after connecting to mysql. If no database selected your query to select or update a table will not work.
Sometimes a web host will require you to specify the MySQL server name and port number. For example if the MySQL server name is db.php-mysql-tutorial.com and the port number is 3306 (the default port number for MySQL) then you you can modify the above code to :
<?php
$dbhost = 'db.php-mysql-tutorial.com:3306';
$dbuser = 'root';
$dbpass = 'password';
$conn = mysql_connect($dbhost, $dbuser, $dbpass) or die ('Error connecting to mysql');
$dbname = 'petstore';
mysql_select_db($dbname);
?>
It's a common practice to place the routine of opening a database connection in a separate file. Then everytime you want to open a connection just include the file. Usually the host, user, password and database name are also separated in a configuration file.
An example of config.php that stores the connection configuration and opendb.php that opens the connection are :
Source code : config.phps , opendb.phps
<?php
// This is an example of config.php
$dbhost = 'localhost';
$dbuser = 'root';
$dbpass = 'password';
$dbname = 'phpcake';
?>
<?php
// This is an example opendb.php
$conn = mysql_connect($dbhost, $dbuser, $dbpass) or die ('Error connecting to mysql');
mysql_select_db($dbname);
?>
So now you can open a connection to mysql like this :
<?php
include 'config.php';
include 'opendb.php';
// ... do something like insert or select, etc
?>
Closing the Connection
The connection opened in a script will be closed as soon as the execution of the script ends. But it's better if you close it explicitly by calling mysql_close() function. You could also put this function call in a file named closedb.php.
Source code : closedb.phps
<?php
// an example of closedb.php
// it does nothing but closing
// a mysql database connection
mysql_close($conn);
?>
Now that you have put the database configuration, opening and closing routines in separate files your PHP script that uses mysql would look something like this :
<?php
include 'config.php';
include 'opendb.php';
// ... do something like insert or select, etc
include 'closedb.php';
?>
For more information see this link
http://php.net/manual/en/function.mysql-connect.php
Jan 14, 2011
