diff --git a/core/lib/Drupal/Core/Config/DatabaseStorage.php b/core/lib/Drupal/Core/Config/DatabaseStorage.php
index 99c638e..fff4a7a 100644
--- a/core/lib/Drupal/Core/Config/DatabaseStorage.php
+++ b/core/lib/Drupal/Core/Config/DatabaseStorage.php
@@ -191,7 +191,7 @@ protected static function schemaDefinition() {
         'collection' => array(
           'description' => 'Primary Key: Config object collection.',
           'type' => 'varchar',
-          'length' => 255,
+          'length' => 78,
           'not null' => TRUE,
           'default' => '',
         ),