Fixes #2212: `yii\gridview\DataColumn` generates incorrect labels when used with…

framework/CHANGELOG.md

@@ -38,6 +38,7 @@ Yii Framework 2 Change Log
 - Bug #1998: Unchecked required checkbox never pass client validation (klevron)
 - Bug #2084: AssetController adjusting CSS URLs declared at same line fixed (klimov-paul)
 - Bug #2091: `QueryBuilder::buildInCondition()` fails to handle array not starting with index 0 (qiangxue)
+- Bug #2212: `yii\gridview\DataColumn` generates incorrect labels when used with nosql DB and there is no data (qiangxue)
 - Bug: Fixed `Call to a member function registerAssetFiles() on a non-object` in case of wrong `sourcePath` for an asset bundle (samdark)
 - Bug: Fixed incorrect event name for `yii\jui\Spinner` (samdark)
 - Bug: Json::encode() did not handle objects that implement JsonSerializable interface correctly (cebe)

framework/grid/DataColumn.php

@@ -9,7 +9,7 @@ namespace yii\grid;
 
 use yii\base\Model;
 use yii\data\ActiveDataProvider;
-use yii\db\ActiveQuery;
+use yii\db\ActiveQueryInterface;
 use yii\helpers\ArrayHelper;
 use yii\helpers\Html;
 use yii\helpers\Inflector;
@@ -90,7 +90,7 @@ class DataColumn extends Column
 		$provider = $this->grid->dataProvider;
 
 		if ($this->label === null) {
-			if ($provider instanceof ActiveDataProvider && $provider->query instanceof ActiveQuery) {
+			if ($provider instanceof ActiveDataProvider && $provider->query instanceof ActiveQueryInterface) {
 				/** @var Model $model */
 				$model = new $provider->query->modelClass;
 				$label = $model->getAttributeLabel($this->attribute);