Connection with database - PDO

In official documentation :

  

PDO :: MYSQL_ATTR_INIT_COMMAND (integer)

     

Command to execute when connecting to MySQL server. Will be run again when reconnecting.

     

Note that this constant can only be used in the driver_options array when   build a new database handler.

That is, it is a mysql command that will run only once per connection as soon as you connect (or reconnect) to the server.

Example usage:

$db = new PDO('mysql:dbname=mydb;host=localhost;port=3306', $user, $pass, 
    array(PDO::MYSQL_ATTR_INIT_COMMAND =>  "SET NAMES 'UTF8'")
);

The SET NAMES 'UTF8' command will be run once whenever a new connection is started.

charset

  

In versions prior to PHP 5.3.6, this element was ignored by   silent form. The same behavior may be partially   replicated with the PDO :: MYSQL_ATTR_INIT_COMMAND option, as well as the   example below demonstrates.

** Setting the character set to UTF-8 before PHP 5.3.6 **

<?php
    $dsn = 'mysql:host=localhost;dbname=testdb';
    $username = 'username';
    $password = 'password';
    $options = array(
        PDO::MYSQL_ATTR_INIT_COMMAND => 'SET NAMES utf8',
    ); 

    $dbh = new PDO($dsn, $username, $password, $options);
?>

With PDO::MYSQL_ATTR_INIT_COMMAND let's be just one that concerns the charset used by MYSQL, which will be UTF8.