Symfony-在EntityType querybuilder的水合过程中丢弃关联字段

My Symfony(3.3)表单EntityType显示为选择输入,并列出数据库中的所有客户端。客户端实体使用延迟模式与其他几个实体相关联。
渲染选择框时,发出204 DB查询。我怀疑表单组件会针对每个查询结果调用setter,从而导致加载许多额外的数据库查询。

那么,这种用例的实现方式是什么?

以下是我迄今为止尝试的内容:

    $builder->add('parent', EntityType::class, [
        'class' => Client::class,
        ,'required' => false
        ,'multiple' => false
        ,'query_builder' => function (EntityRepository $er) {
            $qb = $er ->createQueryBuilder('c')
            // All I want doctrine to fetch are the following fields
                ->select('PARTIAL c.{id,uuid,name,shortName}');
            // I expected this flag to help but it does not change the total amount of queries executed
            $qb->getQuery()->setHint(Query::HINT_FORCE_PARTIAL_LOAD, true);
            return $qb;
        }
    ])…