php 在 yii2 Activerecord 中获取关系表中的计数
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get count in relation table in yii2 Activerecord
提问by Araz Jafaripur
I have two table for post and user. I want to show post count of user in users list gridview. In yii 1 I use this in model to define a relation for this purpose:
我有两个表用于帖子和用户。我想在用户列表 gridview 中显示用户的帖子数。在 yii 1 中，我在模型中使用它来为此目的定义一个关系：
'postCount' => array(self::STAT, 'Post', 'author',
'condition' => 'status = ' . Post::ACTIVE),
...
User:find...().with('postCount').....
But i don't know how to implement this in Yii2 to get count of post in User:find():with('...') to show in gridview.
Anyone try this in yii2?
但我不知道如何在 Yii2 中实现它以获取 User:find():with('...') 中的帖子数以显示在 gridview 中。
有人在 yii2 中尝试过吗？
回答by brdflp
Here is an example of what I did and it seems to work fine so far. It was used to get a count of comments on a post. I simply used a standard active record count and created the relation with the where statement using $this->id and the primary key of the entry its getting a count for.
这是我所做的一个例子，到目前为止它似乎工作正常。它用于获取对帖子的评论计数。我只是使用了一个标准的活动记录计数，并使用 $this->id 和条目的主键创建了与 where 语句的关系，它得到了计数。
public function getComment_count()
{
return Comment::find()->where(['post' => $this->id])->count();
}
Just a passing it along...
只是传递而已...
回答by Ali MasudianPour
You can try the code below:
你可以试试下面的代码：
User::find()->joinWith('posts',true,'RIGHT JOIN')->where(['user.id'=>'posts.id'])->count();
Or if you want to specify a user count:
或者，如果您想指定用户数：
//user id 2 for example
User::find()->joinWith('posts',true,'RIGHT JOIN')->where(['user.id'=>'posts.id','user.id'=>2])->count();
Please note that, postsis a relation defined in your Usermodel like below:
请注意，posts是您的User模型中定义的关系，如下所示：
public function getPosts()
{
return $this->hasMany(Post::className(), ['user_id' => 'id']);
}
回答by Bruno de Oliveira
Well still I think for those who it may concern, if you JUST want the count a select and not the data it will be better use this instead imho:
好吧，我仍然认为对于那些可能关心的人来说，如果你只是想要一个选择而不是数据，那么最好使用它而不是 imho：
$count = (new \yii\db\Query())
->select('count(*)')
->from('table')
->where(['condition'=>'value'])
->scalar();
echo $count;
