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MySQLi - Connection

MySQL Connection Using MySQL Binary

You can estabpsh the MySQL database using the mysql binary at the command prompt.

Example

Here is a simple example to connect to the MySQL server from the command prompt −


[root@host]# mysql -u root -p
Enter password:******

This will give you the mysqp command prompt where you will be able to execute any SQL command. Following is the result of above command −

The following code block shows the result of above code −


Welcome to the MySQL monitor.  Commands end with ; or g.
Your MySQL connection id is 2854760 to server version: 5.0.9

Type  help;  or  h  for help. Type  c  to clear the buffer.

In the above example, we have used root as a user but you can use any other user as well. Any user will be able to perform all the SQL operations, which are allowed to that user.

You can disconnect from the MySQL database any time using the exit command at mysql> prompt.


mysql> exit
Bye

MySQL Connection Using PHP Script

PHP provides mysqp contruct or mysqp_connect() function to open a database connection. This function takes six parameters and returns a MySQL pnk identifier on success or FALSE on failure.

Syntax


$mysqp = new mysqp($host, $username, $passwd, $dbName, $port, $socket);

Sr.No.	Parameter & Description
1	$host Optional − The host name running the database server. If not specified, then the default value will be localhost:3306.
2	$username Optional − The username accessing the database. If not specified, then the default will be the name of the user that owns the server process.
3	$passwd Optional − The password of the user accessing the database. If not specified, then the default will be an empty password.
4	$dbName Optional − database name on which query is to be performed.
5	$port Optional − the port number to attempt to connect to the MySQL server..
6	$socket Optional − socket or named pipe that should be used.

You can disconnect from the MySQL database anytime using another PHP function close().

Syntax


$mysqp→close();

Example

Try the following example to connect to a MySQL server −

Copy and paste the following example as mysql_example.php −


<html>
   <head>
      <title>Connecting MySQL Server</title>
   </head>
   <body>
      <?php
         $dbhost =  localhost ;
         $dbuser =  root ;
         $dbpass =  root@123 ;
         $mysqp = new mysqp($dbhost, $dbuser, $dbpass);
         
         if($mysqp→connect_errno ) {
            printf("Connect failed: %s<br />", $mysqp→connect_error);
            exit();
         }
         printf( Connected successfully.<br /> );
         $mysqp→close();
      ?>
   </body>
</html>

Output

Access the mysql_example.php deployed on apache web server and verify the output.


Connected successfully.

MySQLi - Connection

MySQL Connection Using MySQL Binary

Example

MySQL Connection Using PHP Script

Syntax

Syntax

Example

Output

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