Ticket #2699: 2699.5.diff

wp-admin/includes/upgrade.php

@@ -1672 +1672 @@
         // Delete duplicate options.  Keep the option with the highest option_id.
         $delete_options = $wpdb->get_col("SELECT o1.option_id FROM $wpdb->options AS o1 JOIN $wpdb->options AS o2 ON o2.option_name = o1.option_name AND o2.option_id > o1.option_id");
         if ( !empty($delete_options) ) {
-                $delete_options = implode("', '", $delete_options);
+                $delete_options = implode(',', $delete_options);
                 $wpdb->query("DELETE FROM $wpdb->options WHERE option_id IN ($delete_options)");
         }