Symfony 2 cache Doctrine query results

Question

I am working on a Symfony2 project using Doctrine. I want to optimise the API performance by adding cache to queries.

I have looked at few options such as:

• Symfony annotation cache
• Doctrine cache
• Memcache

Not to sure with which one I should go but to me it seems like caching data at Doctrine level would be most suitable.

Saying that I would like someone to help me or guide me how to set up Doctrine cache and explain how it exactly works.

I.e I have this query:

class QueryFactory

    protected $connect;

    public function __construct(Connection $connection)
    {
        $this->connect = $connection;
    }

    private function myQuery()
    {
        return $this->connect->createQueryBuilder()
            ->select('user_id')
            ->from('users', 'u')
            ->where('u.user_id = 2');
    }
}

How would I add a cache to this query? Is there any Doctrine library I need to inject any thing I need to use?

Solution

In doctrine to cache queries or results you can do the following:

private function myQuery()
{
    return $this->connect->createQueryBuilder()
        ->select('user_id')
        ->from('users', 'u')
        ->where('u.user_id = 2')
        ->getQuery()
        ->useQueryCache(true)    // here
        ->useResultCache(true);  // and here
}

Check doc for more info about these methods. This will make your cache driver working - doesn't matter what driver you are using.

To configure Symfony to use specific query driver you need to adjust your settings in config.yml - check this to see complete list of options. What is important in your cache is (this is apc configuration example):

entity_managers:
        some_em:
            query_cache_driver: apc
            metadata_cache_driver: apc
            result_cache_driver: apc

You might also want to check this and this blog entries