/**
* Generate settings for comments caching
*
* @param string $model comment's model name
* @param int $model_id comment's model id
* @param int $duration
* @return array
*/
public static function getCacheProperties($model, $model_id = '', $duration = 3600)
{
$tableName = Comment::tableName();
return ['duration' => $duration, 'dependency' => ['class' => 'yii\\caching\\DbDependency', 'sql' => "SELECT COUNT(*) FROM {$tableName} " . "WHERE `model` = '{$model}' AND `model_id` = '{$model_id}'"]];
}