diff --git a/core/modules/entity_reference/lib/Drupal/entity_reference/Plugin/field/field_type/ConfigurableEntityReferenceItem.php b/core/modules/entity_reference/lib/Drupal/entity_reference/Plugin/field/field_type/ConfigurableEntityReferenceItem.php
index edf1530..1c7ea0e 100644
--- a/core/modules/entity_reference/lib/Drupal/entity_reference/Plugin/field/field_type/ConfigurableEntityReferenceItem.php
+++ b/core/modules/entity_reference/lib/Drupal/entity_reference/Plugin/field/field_type/ConfigurableEntityReferenceItem.php
@@ -10,6 +10,7 @@
 use Drupal\Core\Annotation\Translation;
 use Drupal\Core\Entity\Annotation\FieldType;
 use Drupal\Core\Entity\Plugin\DataType\EntityReferenceItem;
+use Drupal\field\FieldInterface;
 
 /**
  * Plugin implementation of the 'entity_reference' field type.
@@ -41,6 +42,47 @@ class ConfigurableEntityReferenceItem extends EntityReferenceItem {
   /**
    * {@inheritdoc}
    */
+  public static function schema(FieldInterface $field) {
+    $schema = array(
+      'columns' => array(
+        'target_id' => array(
+          'description' => 'The ID of the target entity.',
+          'type' => 'int',
+          'unsigned' => TRUE,
+          'not null' => TRUE,
+        ),
+        'revision_id' => array(
+          'description' => 'The revision ID of the target entity.',
+          'type' => 'int',
+          'unsigned' => TRUE,
+          'not null' => FALSE,
+        ),
+      ),
+      'indexes' => array(
+        'target_id' => array('target_id'),
+      ),
+    );
+
+    // Create a foreign key to the target entity type base type.
+    $entity_manager = \Drupal::service('entity.manager');
+    if (is_subclass_of($entity_manager->getControllerClass($field['settings']['target_type'], 'storage'), 'Drupal\Core\Entity\DatabaseStorageController')) {
+      $entity_info = $entity_manager->getDefinition($field['settings']['target_type']);
+
+      $base_table = $entity_info['base_table'];
+      $id_column = $entity_info['entity_keys']['id'];
+
+      $schema['foreign keys'][$base_table] = array(
+        'table' => $base_table,
+        'columns' => array('target_id' => $id_column),
+      );
+    }
+
+    return $schema;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
   public function getPropertyDefinitions() {
     // Definitions vary by entity type and bundle, so key them accordingly.
     $key = $this->definition['settings']['target_type'] . ':';