diff --git a/tools/copy-comment-to-commentcontent.sql b/tools/copy-comment-to-commentcontent.sql
new file mode 100644
index 0000000..9f5a65a
--- /dev/null
+++ b/tools/copy-comment-to-commentcontent.sql
@@ -0,0 +1,63 @@
+-- Copyright 2016 The Chromium Authors. All Rights Reserved.
+--
+-- Use of this source code is governed by a BSD-style
+-- license that can be found in the LICENSE file or at
+-- https://developers.google.com/open-source/licenses/bsd
+
+
+DROP PROCEDURE IF EXISTS CopyCommentToCommentContent;
+
+delimiter //
+
+CREATE PROCEDURE CopyCommentToCommentContent(
+    IN in_start INT, IN in_stop INT, IN in_step INT)
+BEGIN
+  comment_loop: LOOP
+    IF in_start >= in_stop THEN
+      LEAVE comment_loop;
+    END IF;
+
+    SELECT in_start AS StartingAt;
+    SELECT count(*)
+    FROM Comment
+    WHERE Comment.id >= in_start
+    AND Comment.id < in_start + in_step;
+
+    INSERT INTO CommentContent (comment_id, content, inbound_message)
+    SELECT id, content, inbound_message
+    FROM Comment
+    WHERE Comment.id >= in_start
+    AND Comment.id < in_start + in_step;
+
+    SET in_start = in_start + in_step;
+
+  END LOOP;
+
+END;
+
+
+//
+
+
+delimiter ;
+
+
+-- Copy and paste these individually and verify that the site is still responsive.
+-- the first one, takes about 30 sec, then 4-7 minutes for each of the rest.
+-- CALL CopyCommentToCommentContent(           0, 13 * 1000000, 10000);
+-- CALL CopyCommentToCommentContent(13 * 1000000, 16 * 1000000, 10000);
+-- CALL CopyCommentToCommentContent(16 * 1000000, 17 * 1000000, 10000);
+-- CALL CopyCommentToCommentContent(17 * 1000000, 18 * 1000000, 10000);
+-- CALL CopyCommentToCommentContent(18 * 1000000, 19 * 1000000, 10000);
+-- CALL CopyCommentToCommentContent(19 * 1000000, 20 * 1000000, 10000);
+-- CALL CopyCommentToCommentContent(20 * 1000000, 21 * 1000000, 10000);
+-- CALL CopyCommentToCommentContent(21 * 1000000, 22 * 1000000, 10000);
+-- CALL CopyCommentToCommentContent(22 * 1000000, 23 * 1000000, 10000);
+-- CALL CopyCommentToCommentContent(23 * 1000000, 24 * 1000000, 10000);
+-- CALL CopyCommentToCommentContent(24 * 1000000, 25 * 1000000, 10000);
+-- CALL CopyCommentToCommentContent(25 * 1000000, 26 * 1000000, 10000);
+-- CALL CopyCommentToCommentContent(26 * 1000000, 27 * 1000000, 10000);
+-- CALL CopyCommentToCommentContent(27 * 1000000, 28 * 1000000, 10000);
+-- CALL CopyCommentToCommentContent(28 * 1000000, 29 * 1000000, 10000);
+-- CALL CopyCommentToCommentContent(29 * 1000000, 30 * 1000000, 10000);
+-- CALL CopyCommentToCommentContent(30 * 1000000, 40 * 1000000, 10000);