diff --git a/DependencyInjection/Configuration.php b/DependencyInjection/Configuration.php
index <HASH>..<HASH> 100644
--- a/DependencyInjection/Configuration.php
+++ b/DependencyInjection/Configuration.php
@@ -93,9 +93,10 @@ class Configuration implements ConfigurationInterface
                         ->defaultValue(array('name', 'type', 'visible'))
                         ->prototype('scalar')
                             ->validate()
-                            ->ifNotInArray(array('id', 'parent_id', 'name', 'thumbnail', 'type', 'visible', 'owner', 'modified', 'published', 'priority', 'section'))
-                                ->thenInvalid('Invalid column name "%s"')
+                            ->ifTrue(function ($v) { return !is_string($v); })
+                                ->thenInvalid('Column identifier should be a string')
                             ->end()
+                            ->cannotBeEmpty()
                         ->end()
                     ->end()
                     ->arrayNode('categories')
Do not force what columns should be available