Symfony2 doctrine clear cache

app/console

will list how you can do it

 app/console doctrine:cache:clear-metadata 
 app/console doctrine:cache:clear-query  
 app/console doctrine:cache:clear-result 

for symfony 3+:

 php bin/console

and list of comand (for copy/past from project directory):

 php bin/console doctrine:cache:clear-metadata 
 php bin/console doctrine:cache:clear-query  
 php bin/console doctrine:cache:clear-result

If you want to do it within your code (from Doctrine's documentation) :

If you simply want to delete all cache entries you can do so with the deleteAll() method.

    <?php
    $cacheDriver = new \Doctrine\Common\Cache\ArrayCache();
    $deleted = $cacheDriver->deleteAll();

In case you use APC, you could also just call the code

<?php
$deleted = apc_clear_cache() && apc_clear_cache('user');

in a php page on the same server. This is what deleteAll() method in Antho's answer does, but you do not depend on the Doctrine Classes. Btw: the complete cache will be flushed - just in case you use it for non-Doctrine stuff.