diff --git a/core/lib/Drupal/Core/Entity/Query/Sql/Tables.php b/core/lib/Drupal/Core/Entity/Query/Sql/Tables.php
index efed751..2277900 100644
--- a/core/lib/Drupal/Core/Entity/Query/Sql/Tables.php
+++ b/core/lib/Drupal/Core/Entity/Query/Sql/Tables.php
@@ -142,7 +142,7 @@ public function addField($field, $type, $langcode) {
               $next = $specifiers[$key + 1];
             }
             else {
-              $column = '?';
+              $column = '_delta';
             }
           }
           // Is this a field column?
diff --git a/core/lib/Drupal/Core/Entity/Sql/DefaultTableMapping.php b/core/lib/Drupal/Core/Entity/Sql/DefaultTableMapping.php
index ebb0552..d8377d5 100644
--- a/core/lib/Drupal/Core/Entity/Sql/DefaultTableMapping.php
+++ b/core/lib/Drupal/Core/Entity/Sql/DefaultTableMapping.php
@@ -146,14 +146,16 @@ public function getColumnNames($field_name) {
   public function getFieldColumnName(FieldStorageDefinitionInterface $storage_definition, $property_name) {
     $field_name = $storage_definition->getName();
 
-    if ($property_name == '?') {
-      return 'delta';
-    }
-    elseif ($this->allowsSharedTableStorage($storage_definition)) {
+    if ($this->allowsSharedTableStorage($storage_definition)) {
       $column_name = count($storage_definition->getColumns()) == 1 ? $field_name :  $field_name . '__' . $property_name;
     }
     elseif ($this->requiresDedicatedTableStorage($storage_definition)) {
-      $column_name = !in_array($property_name, $this->getReservedColumns()) ? $field_name . '_' . $property_name : $property_name;
+      if ($property_name == '_delta') {
+        $column_name = 'delta';
+      }
+      else {
+        $column_name = !in_array($property_name, $this->getReservedColumns()) ? $field_name . '_' . $property_name : $property_name;
+      }
     }
     else {
       throw new SqlContentEntityStorageException(String::format('Column information not available for the "@field_name" field.', array('@field_name' => $field_name)));