什么是学说水合作用?

时间:2010-04-18 09:35:16

标签: php doctrine hydration

我在学说的文档中读到过水合作用,但我仍然无法理解它是什么。

有人可以解释一下吗?

2 个答案:

答案 0 :(得分:90)

水合作用是一种用于返回查询结果的方法。例如:

  1. HYDRATE_ARRAY - 这将返回一个由另一个数组表示的记录数组:

    $q = Doctrine_Query::create()
       ->from('Post p')
       ->setHydrationMode(Doctrine::HYDRATE_ARRAY);
    
    $resultSet = $q->execute(); // $resultSet is an array
    
    foreach ($resultSet as $post) {
        // $post is an array
        echo $post['title'];
    }
    
  2. HYDRATE_RECORD - 这会返回一个对象集合(Doctrine_Collection):

    $q = Doctrine_Query::create()
       ->from('Post p')
       ->setHydrationMode(Doctrine::HYDRATE_RECORD); // Unnecessary, HYDATE_RECORD is default method
    
    $resultSet = $q->execute(); // $resultSet is an Doctrine_Collection object
    
    foreach ($resultSet as $post) {
        // $post is an Post object
        echo $post->getTitle();
        echo $post['title']; // Each Doctrine's Model object implements ArrayAccess interface so this is possible
        echo $post->myCustomMethod();
    }
    
  3. HYDRATE_SINGULAR_SCALAR - 将返回查询结果第一列的值:

     $q = Doctrine_Query::create()
       ->select('p.created_at')
       ->from('Post p')
       ->where('p.id = ?', 321)
       ->setHydrationMode(Doctrine::HYDRATE_SINGULAR_SCALAR); 
    
    $createdAt = $q->execute(); // $createdAt has value of first column from first record from result set (eg.: 2008-04-06 21:22:35)
    
  4. 还有一些方法,您可以在文档中阅读每个方法。

答案 1 :(得分:3)

$q->fetchOne(array(), Doctrine_Core::HYDRATE_ARRAY);

It will return just a simple array instead of a doctrine collection object.