什么是 Doctrine 水合作用? [英] What is Doctrine hydration?

问题描述

我在学说的文档中阅读了有关水合作用的内容，但我仍然无法理解它是什么.

I've read about hydration in doctrine's documentation but I still can't understand what it is.

谁能解释一下?

推荐答案

Hydration是一种用于返回查询结果的方法.例如:

Hydration is a method used to return query results. For example:

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

1. HYDRATE_ARRAY - This will return you an array of records that are represented by another array:

$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'];
}

HYDRATE_RECORD - 这将返回一个集合(Doctrine_Collection) 对象:

HYDRATE_RECORD - This will return you an collection (Doctrine_Collection) of objects:

$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();
}

HYDRATE_SINGULAR_SCALAR - 将返回查询结果第一列的值:

HYDRATE_SINGULAR_SCALAR - Will return the value of first column of query's result:

 $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)

还有更多方法，您可以在文档中阅读每个方法.

There is a few more methods , you can read about each in documentation.

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