Doctrine is already shipped with two implementations for the "PostConnect" event:
* `Doctrine\DBAL\Event\Listeners\OracleSessionInit` allows to specify any number of Oracle Session related enviroment variables that are set right after the connection is established.
* `Doctrine\DBAL\Event\Listeners\MysqlSessionInit` allows to specify the Charset and Collation of the Client Connection if these options are not configured correctly on the MySQL server side.
You can register events by subscribing them to the `EventManager` instance