Ticket #21272: for-update-keys.diff

wp-admin/includes/upgrade.php

@@ -1628 +1628 @@
                 foreach ( (array) $indices as $index ) {
                         // Push a query line into $cqueries that adds the index to that table
                         $cqueries[] = "ALTER TABLE {$table} ADD $index";
-                        $for_update[$table.'.'.$fieldname] = 'Added index '.$table.' '.$index;
+                        $for_update[] = 'Added index '.$table.' '.$index;
                 }
 
                 // Remove the original table creation query from processing