通过将DQL示例改编为DBAL，我找到了解决方案。诀窍是获取子查询的原始SQL，将其包装在方括号中，然后将其联接。子查询中使用的参数必须在主查询中设置：
$subSelect = $connection->createQueryBuilder() ->select(array('userSurveyID', 'MIN(timestamp) timestamp')) ->from('user_survey_status_entries') // Instead of setting the parameter in the main query below, it could be quoted here: // ->where('status = ' . $connection->quote(UserSurveyStatus::ACCESSED)) ->where('status = :status') ->groupBy('userSurveyID');$select = $connection->createQueryBuilder() ->select($selectColNames) ->from('user_surveys', 'us') // Get raw subquery SQL and wrap in brackets. ->leftJoin('us', sprintf('(%s)', $subSelect->getSQL()), 'firstAccess', 'us.userSurveyID = firstAccess.userSurveyID') // Parameter used in subquery must be set in main query. ->setParameter('status', UserSurveyStatus::ACCESSED) ->where('us.surveyID = :surveyID')->setParameter('surveyID', $surveyID);
