Yii2 filter Sum data in GridView - php

Question

I'm trying display and filter data which I got via SQL SUM operator.
I have 2 table employee and department. Table employee contains department_id filed and salary filed. I need display all department and total SUM salary for every department.
I followed this guide, but GridView does not display any data.
Here is action:
public function actionIndex()
{
$searchModel = new DepartmentFrontendSearch();
$dataProvider = $searchModel->search(Yii::$app->request->queryParams);
return $this->render('index',
[
'dataProvider' => $dataProvider,
'searchModel' => $searchModel,
]
);
}
Model:
class DepartmentFrontendSearch extends DepartmentFrontend
public $employee_count;
public $salary;
public function rules() {
return [
[['employee_count','salary','name'], 'safe']
];
}
public function search($params) {
$query = DepartmentFrontend::find();
$subQuery = Employee::find()
->select('department_id, SUM(salary) as salary_amount')
->groupBy('department_id');
$query->leftJoin(['salarySum' => $subQuery], 'salarySum.department_id = id');
$dataProvider = new ActiveDataProvider([
'query' => $query,
]);
$dataProvider->setSort([
'attributes' => [
'name',
'salary'
]
]);
$this->load($params);
if (!$this->validate()) {
return $dataProvider;
}
$query->andFilterWhere(['like', 'name', $this->name]);
$query->andWhere(['salarySum.salary_amount' => $this->salary]);
return $dataProvider;
}
GRID:
echo GridView::widget([
'dataProvider' => $dataProvider,
'filterModel' => $searchModel,
'columns' => [
['class' => 'yii\grid\SerialColumn'],
'salary_amount',
'employee_count',
'name',
],
]);
So, can anybody tell me what I did wrong?

Answer 1

If You need a filter for the alias salary_amount you should add a specific var for this (do the fact salary_amount is an alias for sum(salary) the var $salary is not useful)
public $employee_count;
public $salary;
public $salary_amount;
otherwise use salary as alias too
the in your filter you are using
$query->andWhere(['salarySum.salary_amount' => $this->salary]);
But salary_amount is the result of an aggregation so you should use having(SUM(salary) = $this->salary_amount)
$query->having('SUM(salary) = ' . $this->salary_amount);