Question

我想用Doctrine MongoDB ODM获取这个mongodb命令的结果：

db.posts.find({_id: 3}, {comments: {$slice: [0, 5]}})

我一直在寻找它，但在文档中都找不到任何东西。如果您有任何想法，请帮助，谢谢。

以下是我的文档类：

/** @ODM\Document(db="dbname" collection="posts") */
class Posts{

    /** @ODM\Id */
    private $_id;

    /** @ODM\Field(type="string") */
    private $some_field;

    /** @ODM\EmbedMany(targetDocument="Comment") */
    private $comments = array();

    public function getSomeField() { return $this->some_field; }
    public function setSomeField($content) { $this->some_field = $content; }

    public function getComments() { return $this->comments; }
    public function addComment(Comment $comment) { $this->comments[] = $comment; }
}

/** @ODM\EmbeddedDocument */
class Comment {

    /** @ODM\Field(type="string") */
    private $timeStamp;

    /** @ODM\Field(type="string") */
    private $message;

    /** @ODM\ReferenceOne(targetDocument="Users", simple=true) */
    private $user_ref;

    public function getTimeStamp() { return $this->timeStamp; }
    public function setTimeStamp($str) { $this->timeStamp = $str;}

    public function getMessage() { return $this->message; }
    public function setMessage($str) { $this->message = $str; }

    public function getUser() { return $this->user_ref; }
    public function setUser(Users $user) { $this->user_ref = $user; }

}

Answer 1

虽然有关查询构建器->select()的文档并未详细介绍细节或方法，但以下代码将允许您运行命令：

$qb = $this->dm->createQueryBuilder(Posts::class)
        ->selectSlice('comments', 0, 5)
        ->field('_id')->equals(3);
$query = $qb->getQuery();
$results = $query->execute();

如何使用mongodb-odm从嵌入式文档中获取有限数量的字段？

1 个答案: