PDO + MySQL and broken UTF-8 encoding

Warning: This answer applies to PHP 5.3.5 and lower. Do not use it for PHP version 5.3.6 (released in March 2011) or later.

Compare with Palec's answer here.

Use:

$pdo = new PDO( 
    'mysql:host=hostname;dbname=defaultDbName', 
    'username', 
    'password', 
    array(PDO::MYSQL_ATTR_INIT_COMMAND => "SET NAMES utf8") 
); 

It forces UTF-8 on the PDO connection. It worked for me.

You have to set the correct character set for the connection. Add the charset=utf8 option to the DSN (this is MySQL-specific!)

$pdo = new PDO(
    'mysql:host=hostname;dbname=defaultDbName;charset=utf8',
    'username',
    'password'
);

However, in PHP versions before 5.3.6 (released in March 2011), you must use a workaround as the charset option in the DSN is not supported.

$pdo = new PDO(
    'mysql:host=hostname;dbname=defaultDbName',
    'username',
    'password',
    array(PDO::MYSQL_ATTR_INIT_COMMAND => "SET NAMES utf8")
);

All attempts like:

PDO::MYSQL_ATTR_INIT_COMMAND =>"SET NAMES 'utf8mb4' COLLATE 'utf8mb4_unicode_ci' "

or

$this->connection = new PDO('mysql:host='.DBHOST.';dbname='.DBNAME.';charset=utf8', DBUSER, DBPASS, self::$opt);

or

$this->connection->exec("set names utf8");

still generated unreadable text mess.

In my case, the cause of the problem was: htmlentities used prior to inserting data into a database. Cyrillic letters were destroyed completely.

Try setting the default_charset value in php.ini to UTF-8. Or you can set it using the ini_set function.

Also, if the input is coming through form submissions, make sure your web pages are set to UTF-8 using the meta tag.