Question

我有一个post表，它的架构是这样的：

CREATE TABLE IF NOT EXISTS `post` (
  `id` bigint(20) NOT NULL AUTO_INCREMENT,
  `user_id` bigint(20) DEFAULT NULL,
  `site_id` bigint(20) DEFAULT NULL,
  `parent_id` bigint(20) DEFAULT NULL,
  `title` longtext COLLATE utf8_turkish_ci NOT NULL,
  `status` varchar(20) COLLATE utf8_turkish_ci NOT NULL,
  PRIMARY KEY (`id`),
  KEY `IDX_5A8A6C8DA76ED395` (`user_id`),
  KEY `IDX_5A8A6C8DF6BD1646` (`site_id`),
  KEY `IDX_5A8A6C8D727ACA70` (`parent_id`),
) ENGINE=InnoDB  DEFAULT CHARSET=utf8 COLLATE=utf8_turkish_ci AUTO_INCREMENT=16620 ;

我正在使用这个DQL来获取一个帖子，它是孩子们：

$post = $this->_diContainer->wordy_app_doctrine->fetch(
           "SELECT p,c FROM Wordy\Entity\Post p LEFT JOIN p.children c WHERE p.site = :site AND p.id = :id AND p.language = :language AND p.status != 'trashed'  AND c.status != 'trashed' ORDER BY c.title",
           array(
               'params' => array(
               'id' => $id,
               'site' => $this->_currentSite['id'],
               'language' => $this->_currentLanguage->code,
           )
       )
   );

我要做的是：获取一个帖子及其所有孩子。标准是，不包括破坏的帖子或被遗弃的儿童。

但是当我使用一个甚至没有孩子的帖子运行此查询时，返回的结果集为空。

当我从查询中删除c.status != 'trashed'部分时，一切正常但我也会收到删除的帖子。

提前谢谢。

编辑：这是给定DQL的SQL输出：

SELECT p0_.id AS id0, p0_.title AS title5, p0_.status AS status8, p0_.parent_id AS parent_id9, p1_.id AS id15, p1_.title AS title20, p1_.status AS status23, p1_.parent_id AS parent_id24 FROM post p0_ LEFT JOIN post p1_ ON p0_.id = p1_.parent_id WHERE p0_.site_id = ? AND p0_.id = ? AND p0_.language = ? AND p0_.status <> 'trashed' ORDER BY p1_.title ASC

Answer 1

您的长条件WHERE在加入后正在进行AND运算，并且没有任何内容通过所有检查。将连接内容移动到ON子句中，并在WHERE子句中保留c.trashed检查。尝试这样的事情：

SELECT p,c FROM Wordy\Entity\Post p LEFT JOIN children c ON p.site = :site AND p.id = :id AND p.language = :language AND p.status != 'trashed' AND p.id = c.parent_id  WHERE   c.status != 'trashed' ORDER BY c.title

Answer 2

您忘记了left join syntax的ON条款。

Answer 3

我想我解决了自己的问题。

只需在with字段而不是join子句中使用where子句，如下所示：

"SELECT p,c FROM Wordy\Entity\Post p LEFT JOIN p.children c WITH c.status != 'trashed' WHERE p.site = :site........."

Left Join with Where子句返回空结果

3 个答案: