php - 使用 doctrine 2 DBAL 加入子查询

Question

我正在重构 Zend Framework 2 应用程序以使用 doctrine 2.5 DBAL 而不是 Zend_DB (ZF1)。我有以下 Zend_Db 查询:

$subSelect = $db->select()
    ->from('user_survey_status_entries', array('userSurveyID', 'timestamp' => 'MIN(timestamp)'))
    ->where('status = ?', UserSurveyStatus::ACCESSED)
    ->group('userSurveyID');


$select = $db->select()
    // $selectColNames contains columns both from the main query and 
    // the subquery (e.g. firstAccess.timestamp AS dateFirstAccess).
    ->from(array('us' => 'user_surveys'), $selectColNames)
    ->joinLeft(array('firstAccess' => $subSelect), 'us.userSurveyID = firstAccess.userSurveyID', array())
    ->where('us.surveyID = ?', $surveyID);

这导致以下 MySQL 查询:

SELECT `us`.`userSurveyID`, 
    // More columns from main query `us`
    `firstAccess`.`timestamp` AS `dateFirstAccess`
FROM `user_surveys` AS `us`
LEFT JOIN (
    SELECT `user_survey_status_entries`.`userSurveyID`, 
            MIN(timestamp) AS `timestamp` 
    FROM `user_survey_status_entries` 
    WHERE (status = 20) 
    GROUP BY `userSurveyID`
) AS `firstAccess` ON us.userSurveyID = firstAccess.userSurveyID 
WHERE (us.surveyID = '10')

我不知道如何使用 doctrine 2.5 查询生成器加入子查询。在主查询中，我需要从子查询中选择列。

我已阅读 here该学说不支持加入子查询。如果仍然如此，我可以使用 doctrine DBAL 的 SQL 查询生成器以另一种方式编写此查询吗？原生 SQL 对我来说可能不是一个好的解决方案，因为这个查询将在代码的后面动态扩展。

Answer 1

我通过调整此 DQL example 找到了解决方案到 DBAL。诀窍是获取子查询的原始 SQL，将其括在括号中，然后加入它。子查询中使用的参数必须在主查询中设置:

重要它是 connection 的 createQueryBuilder 而不是实体管理器之一。

$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);