How to override default platform in Doctrine2 with Symfony2. Example: Force RESTART IDENTITY for TRUNCATE in PostgreSQL when used in "test" environment. This will help you with functional tests as you will always have the same ids.

config_test.yml

doctrine:
    dbal:
        platform_service: postgresql_platform

services:
    postgresql_platform:
        class: Acme\DBAL\Platforms\PostgreSqlPlatform

PostgreSqlPlatform.php

<?php

namespace Acme\DBAL\Platforms;

use Doctrine\DBAL\Platforms\PostgreSqlPlatform as DoctrinePostgreSqlPlatform;

class PostgreSqlPlatform extends DoctrinePostgreSqlPlatform
{
    public function getTruncateTableSQL($tableName, $cascade = false)
    {
        return 'TRUNCATE '.$tableName.' RESTART IDENTITY '.(($cascade)?'CASCADE':'');
    }
}

Thanks!