MySqlTestCase

config.yml

doctrine:
    dbal:
        driver:   pdo_mysql
        host:     "%database_host%"
        port:     "%database_port%"
        dbname:   "%database_name%"
        user:     "%database_user%"
        password: "%database_password%"
        charset:  UTF8

    orm:
        auto_generate_proxy_classes: "%kernel.debug%"
        entity_managers:
            default:
                connection: default
                auto_mapping: false
                mappings:
                    Domain:
                        type: annotation
                        dir: %kernel.root_dir%/../src/Domain
                        prefix: Domain
                        is_bundle: false

mysqltestcase.php

<?php

namespace TimeTracker\ProjectsBundle\Tests\Repository;

use Doctrine\ORM\EntityManager;
use Doctrine\ORM\Tools\SchemaTool;
use Symfony\Bundle\FrameworkBundle\Test\WebTestCase;
use Symfony\Component\DependencyInjection\ContainerInterface;
use Symfony\Component\HttpKernel\Kernel;

class MySqlTest extends WebTestCase
{
    protected static $kernel;

    /**
     * @var EntityManager
     */
    protected $entityManager;

    /**
     * @return ContainerInterface
     */
    protected function getContainer()
    {
        return $this->getKernel()->getContainer();
    }

    /**
     * @return Kernel
     */
    protected function getKernel()
    {
        if (!isset(self::$kernel)) {
            self::$kernel = static::createKernel(
                array(
                    'environment' => 'test'
                )
            );
            self::$kernel->boot();
        }
        return self::$kernel;
    }

    protected function setUp()
    {
        parent::setUp();
        $this->entityManager = $this->getContainer()->get('doctrine.orm.default_entity_manager');
        $this->entityManager->getConnection()->beginTransaction();

        $classes = $this->entityManager->getMetadataFactory()->getAllMetadata();
        $schemaTool = new SchemaTool($this->entityManager);
        $schemaTool->dropSchema($classes);
        $schemaTool->createSchema($classes);
    }

    /**
     * Clean up Kernel usage in this test.
     */
    protected function tearDown()
    {
        $this->entityManager->getConnection()->rollBack();
    }
}