什么是学说水合？

Question

我已经阅读了关于学说文献中的水合作用，但我仍然不明白它是什么。

请问有人能解释一下吗？

Answer 1

水化是一种用于返回查询结果的方法。例如：

1. HYDRATE_ARRAY - 这将返回一组记录由另一个数组表示：

   $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 - 这将返回对象的集合（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 - 将返回第一列查询的值r esult：

   $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) 
   

有几个方法，你可以看到每一个文档。

Answer 2

Doctrine2文档的参考解释HYDRATION： http://www.doctrine-project.org/docs/orm/2.0/en/reference/dql-doctrine-query-language.html#query-result-formats

Answer 3

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

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