Yii2 activerecord从相关表中选择自定义属性

Question

When I'm trying to select custom attributes from record

 $data = Emotion::find()
        ->select('em_id, em_name, tbl_post.post_id, tbl_post.post_header')
        ->where(['em_id' => $id])
        ->joinWith('posts')
        ->one();

I've got an answer model, where related field have full set of table fields. Trace message looks like this:

 app\models\Emotion#1
 ( [yii\db\BaseActiveRecord:_attributes] => 
[ 'em_id' => 4
'em_name' => 'test_em']
[yii\db\BaseActiveRecord:_related] => 
[ 'posts' => 
[ 0 => app\models\Post#2 ( [yii\db\BaseActiveRecord:_attributes] => 
[ 'post_id' => 10
'post_header' => 'some header' 
'post_date' => '2015-06-24 13:40:25', 
'post_descr' => 'Rocco, continue the joke'
'post_content' => 'test content'...

So, maybe i did something wrong or this is a framework issue.

Found a workaround here: Yii2 GitHub issue

Which for my case looks like this:

$data = Emotion::find()
        ->select('em_id, em_name, tbl_post.post_id, tbl_post.post_header')
        ->where(['em_id' => $id])
        ->joinWith('posts')
        ->createCommand()
        ->queryAll();

And the output of this request will be an raw array. Is there an another way to have an ActiveRecord object in a response data?

Answer 1

You should simply modify the relation query, eg :

$data = Emotion::find()
    ->select('em_id, em_name')
    ->where(['em_id' => $id])
    ->with([
        'posts' => function($query) {
            $query->select('post_id, post_header');
        }
    ])->one();

And you don't need joinWith since you don't use posts in the main query.