主義限制打破我的查詢？

Question

我有以下代碼：

$params = array(); 
$query_questions_visibles = questionTable::getInstance()->createQuery("q") 
    ->select("q.*, ua.*, a.*, u.*, c.*") 
    ->leftJoin("q.Answers a") 
    ->leftJoin("a.UserAnswers ua") 
    ->Where("q.blocked = false") 
    ->andWhere("ua.user_id = :user_id") 
->orderBy("q.id DESC") 
->groupBy("q.id"); 

    //Subquery --> Calculates when a question is active or not  
    $format = sfConfig::get("app_datetime_format"); 
    $active_time = date($format, strtotime(sfConfig::get("app_question_active_time"))); 
    $sub_query_is_active = $query_questions_visibles->createSubQuery() 
      ->select("MAX(ua0.created_at)") 
      ->from("question q0") 
      ->leftJoin("q0.Answers a0") 
      ->leftJoin("a0.UserAnswers ua0") 
      ->where("q0.id = q.id");     
    $query_questions_visibles->addSelect("COALESCE((".$sub_query_is_active.") > :active_time, false) as Active"); 

//Set param values 
$params["user_id"] = $guardUser->id; 
$params["active_time"] = $active_time; 

$result = $query_questions_visibles->execute($params); 

上面的代碼按預期工作。

生成的SQL是完整的作品：

SELECT q.id AS q__id, q.user_id AS q__user_id, q.category_id AS q__category_id, q.gender_restriction AS q__gender_restriction, q.question AS q_question, q.photo AS q_photo, q.latitude AS q_latitude, q.longitude AS q_longitude, q.multiple AS q_multiple, q.blocked AS q_blocked, q.created_at AS q__created_at, q.updated_at AS q__updated_at, a.id AS a__id, a.question_id AS a__question_id, a.text AS a_text, u.id AS u_id, u.user_id AS u__user_id, u.answer_id AS u__answer_id, u.created_at AS u__created_at, u.updated_at AS u__updated_at, COALESCE((SELECT MAX(u2.created_at) AS u2__0 FROM question q2 LEFT JOIN answer a2 ON q2.id = a2.question_id LEFT JOIN user_answer u2 ON a2.id = u2.answer_id WHERE (q2.id = q.id)) > :active_time, 0) AS u2__0 FROM question q LEFT JOIN answer a ON q.id = a.question_id LEFT JOIN user_answer u ON a.id = u.answer_id WHERE (q.blocked = 0 AND u.user_id = :user_id) GROUP BY q.id ORDER BY q.id DESC

但是，如果我想限制的結果，我修改端線爲：

$query_questions_visibles->limit(10); 
$result = $query_questions_visibles->execute($params); 

主義拋出一個錯誤：

SQLSTATE[HY093]: Invalid parameter number: number of bound variables does not match number of tokens

at Doctrine_Connection->execute('SELECT DISTINCT q2.id FROM question q2 LEFT JOIN answer a2 ON q2.id = a2.question_id LEFT JOIN user_answer u2 ON a2.id = u2.answer_id WHERE q2.blocked = 0 AND u2.user_id = :user_id GROUP BY q2.id ORDER BY q2.id DESC LIMIT 10', array('user_id' => '1', 'active_time' => '2013-03-17 17:12:12')) in SF_ROOT_DIR\lib\vendor\symfony\lib\plugins\sfDoctrinePlugin\lib\vendor\doctrine\Doctrine\Query.php line 1290 ...

我的目的只是限制查詢到10個結果，¿哪裏是我的COALESCE和MAX功能子查詢？ ¿爲什麼有一個我從未指定過的SELECT DISTINCT？ ¿爲什麼只選擇q.id？

我整天想弄明白，我沒有答案...... 任何想法，爲什麼設置限制原因造成的？

Answer 1

當您添加limit()的學說查詢然後學說內部建立實際上是兩個查詢。第一個根據查詢條件選擇一組有限的不同ID。第二個查詢選擇實際對象，將select限制爲使用第一個查詢找到的id。

與您的查詢的問題是，您使用select部分，這是不是在第一個查詢中使用的內部PARAMS。

我想到的唯一解決方案是將active_time參數的值直接添加到選擇部分，而不使用命名參數。這可能不是最好的解決方案，但我現在無法想象另一種解決方案。該addSelect()不接受額外的參數，如where()確實可能解決這個問題（與where()你可以使用：->where('field > ?', $value)）。