Yii2: sort a relational count column in GridView - php

Question

[EDITED 2]
I'm having hard time to sort by the 'topicCount' which is defined as a relational getter on a model 'Tag'.
A Topic can have a lots of Tag, and wish to sort the Tags by how many Topics containing that Tag.
In my models/Tag.php:
public function getTopicCount()
{
return TopicTag::find()->where(['tag_id' => $this->id])->count();
}
And in my views/tag/index.php:
<?= GridView::widget([
'dataProvider' => $dataProvider,
'columns' => [
'id',
'name',
[
'attribute'=>'topicCount',
'value' => 'topicCount',
],
'created_at',
['class' => 'yii\grid\ActionColumn','template' => '{view}',],
],
]); ?>
And in my controllers/TagController.php:
public function actionIndex()
{
$dataProvider = new ActiveDataProvider([
'query' => Tag::find(),
'sort'=> [
'defaultOrder' => ['id'=>SORT_DESC],
'attributes' => ['id','topicCount'],
],
'pagination' => [
'pageSize' => 100,
],
]);
return $this->render('index', [
'dataProvider' => $dataProvider,
]);
}
And in my models/TagSearch.php:
<?php
namespace common\models;
use Yii;
/**
* This is the model class for table "tags".
*
* #property integer $id
* #property string $name
* #property string $created_at
* #property string $updated_at
*/
class TagSearch extends Tag
{
public $topicCount;
/**
* #inheritdoc
*/
public function rules()
{
return [
[['topicCount'], 'safe']
];
}
public function search($params)
{
// create ActiveQuery
$query = Tag::find();
$query->joinWith(['topicCount']);
$dataProvider = new ActiveDataProvider([
'query' => $query,
]);
$dataProvider->sort->attributes['topicCount'] = [
'asc' => ['topicCount' => SORT_ASC],
'desc' => ['topicCount' => SORT_DESC],
];
if (!($this->load($params) && $this->validate())) {
return $dataProvider;
}
$query->andFilterWhere([
//... other searched attributes here
])
->andFilterWhere(['=', 'topicCount', $this->topicCount]);
return $dataProvider;
}
}
And in the index view I can see the correct topicCount:
but on clicking the topicCount column I get the error:
exception 'PDOException' with message 'SQLSTATE[42703]: Undefined column: 7 ERROR: column "topicCount" does not exist
LINE 1: SELECT * FROM "tags" ORDER BY "topicCount" LIMIT 100
Thanks for any guidance..!
[EDIT]
Following Lucas' advice, I've set my dataProvider query in my $dataProvider like this:
'query' => $query->select(['tags.*','(select count(topic_tags.id) from topic_tags where topic_tags.tag_id=tags.id) topicCount'])->groupBy('tags.id'),
and I got error:
exception 'PDOException' with message 'SQLSTATE[42P01]: Undefined table: 7 ERROR: missing FROM-clause entry for table "tags"
so I reformulated like this:
'query' => $query->from('tags')->leftJoin('topic_tags','topic_tags.tag_id = tags.id')->select(['tags.*','(select count(topic_tags.id) from topic_tags where topic_tags.tag_id=tags.id) topicCount'])->groupBy('tags.id'),
and now I get the result:
apparently the topicCount column is not set, so when I try to sort by it, it returns the error:
exception 'PDOException' with message 'SQLSTATE[42703]: Undefined column: 7 ERROR: column "topicCount" does not exist
but when I try the SQL directly on the DB, it works fine:
so I suppose the problem is in the way Yii handles the alias 'topicCount'?
2nd EDIT
Still the same result without the topicCount set in the Grid view.
I show my TagSearch model, TagController and views/tag/index view file below:
TagSearch
<?php
namespace common\models;
use Yii;
use yii\base\Model;
use yii\data\ActiveDataProvider;
use common\models\Tag;
/**
* TagSearch represents the model behind the search form about `common\models\Tag`.
*/
class TagSearch extends Tag
{
public $topicCount;
/**
* #inheritdoc
*/
public function rules()
{
return [
[['id', 'topicCount'], 'integer'],
[['name', 'created_at', 'updated_at', 'topicCount'], 'safe'],
];
}
/**
* #inheritdoc
*/
public function scenarios()
{
// bypass scenarios() implementation in the parent class
return Model::scenarios();
}
/**
* Creates data provider instance with search query applied
*
* #param array $params
*
* #return ActiveDataProvider
*/
public function search($params)
{
$query = Tag::find();
$dataProvider = new ActiveDataProvider([
'query' => $query->from("tags")->select(["tags.*","(select count(topic_tags.id) from topic_tags where topic_tags.tag_id=tags.id) topicCount"])->groupBy("tags.id"),
]);
$this->load($params);
if (!$this->validate()) {
// uncomment the following line if you do not want to return any records when validation fails
$query->where('0=1');
return $dataProvider;
}
$query->andFilterWhere([
'id' => $this->id,
'topicCount' => $this->topicCount,
'created_at' => $this->created_at,
'updated_at' => $this->updated_at,
]);
$query->andFilterWhere(['like', 'name', $this->name]);
return $dataProvider;
}
}
Tag model
<?php
namespace common\models;
use Yii;
/**
* This is the model class for table "tags".
*
* #property integer $id
* #property integer $topicCount
* #property string $name
* #property string $created_at
* #property string $updated_at
*/
class Tag extends \yii\db\ActiveRecord
{
public $topicCount;
/**
* #inheritdoc
*/
public static function tableName()
{
return 'tags';
}
/**
* #inheritdoc
*/
public function rules()
{
return [
[['topicCount'], 'integer'],
[['name'], 'string'],
[['created_at', 'updated_at'], 'required'],
[['created_at', 'updated_at'], 'safe']
];
}
/**
* #inheritdoc
*/
public function attributeLabels()
{
return [
'id' => 'ID',
'name' => 'Name',
'topicCount' => 'TC',
'created_at' => 'Created At',
'updated_at' => 'Updated At',
];
}
}
TagController
public function actionIndex()
{
$searchModel = new TagSearch();
$myModels = $searchModel->search([]);
return $this->render('index', [
'dataProvider' => $myModels,
]);
}
tags/index
<?= GridView::widget([
'dataProvider' => $dataProvider,
'columns' => [
'id',
'name',
'topicCount',
'created_at',
'updated_at',
['class' => 'yii\grid\ActionColumn','template' => '{view}',],
],
]); ?>
What am I missing?

Answer 1

So resolved following this wiki:
Since in my case I don't use SUM('amount'), I changed to the following and works perfectly:
Tag model:
public function getTopicCount()
{
return $this->hasMany(TopicTag::className(), ["tag_id" => "id"])->count();
}
TagSearch model:
$query = Tag::find();
$subQuery = TopicTag::find()->select('tag_id, COUNT(tag_id) as topic_count')->groupBy('tag_id');
$query->leftJoin(["topicSum" => $subQuery], '"topicSum".tag_id = id');
Just encountered a problem with the generated SQL:
exception 'PDOException' with message 'SQLSTATE[42P01]: Undefined table: 7 ERROR: missing FROM-clause entry for table "topicsum"
This might be a Postgres-specific issue, had to arrange the code so that the generated SQL becomes like this:
SELECT COUNT(*) FROM "tags"
LEFT JOIN (SELECT "tag_id", COUNT(*) as topic_count FROM "topic_tags" GROUP BY "tag_id") "topicSum"
ON "topicSum".tag_id = id
note the double-quotation in "topicSum".tag_id part.
Hope this might be of help for someone using Postgres on Yii2.

Answer 2

You should alter your query to group and select the count instead of working with relations.
$query->groupBy('tags.id')->select(['tags.*','(select count(topic_tag.id) from topic_tag where topic_tag.tag.id=tags.id) topicCount']);
This will add topicCount as a result object in your query, which will make it behave like an ordinary column.
Also as a side note, for a method to act a relation in Yii2, it must return an ActiveQuery object. Your getTopicCount() is returning the count as an int, instead of the query, therefore Yii2 will not treat it like a relation.

Answer 3

Based on this Wiki and #arogachev's answer. I put select property to get tags count
public function search($params)
{
$query = SomeModels::find()
->select('subQueryName.field_count, someModels.*');
// ....
so it will give SQL like this SELECT subQuery.field_count, someModels.* ...
at view (grid),
[
'attribute'=> 'field_count',
],
Thank you #arogachev , you saved me :)

Answer 4

light solution is just reate view in PostgreSQL
and generate model via gii generator using as model and order & find work.
For update & delete use table model for search & index use view model.
For example
for actions update & delete use Tag model
for actions index & view use TagView model.