triggering

news before edit:

+----+---------+---------------------+-----------------+-----------+
| id | user_id | created             | title           | content   |
+----+---------+---------------------+-----------------+-----------+
|  1 |       1 | 2011-11-23 10:52:07 | First news item | B content |
+----+---------+---------------------+-----------------+-----------+

news after edit:
+----+---------+---------------------+-----------------+-----------+
| id | user_id | created             | title           | content   |
+----+---------+---------------------+-----------------+-----------+
|  1 |       1 | 2011-11-23 10:55:16 | First news item | C content |
+----+---------+---------------------+-----------------+-----------+

news_archive after news edit:
+----+---------+---------------------+-----------------+-----------+---------+
| id | user_id | created             | title           | content   | prev_id |
+----+---------+---------------------+-----------------+-----------+---------+
|  1 |       1 | 2011-11-23 10:55:16 | First news item | A content |       1 |
+----+---------+---------------------+-----------------+-----------+---------+

log after news edit:
+----+---------+------------+--------------+---------+---------+--------------------------------------------------+---------------------+
| id | user_id | table_name | user_comment | prev_id | next_id | log_comment                                      | created             |
+----+---------+------------+--------------+---------+---------+--------------------------------------------------+---------------------+
|  1 |       1 | news       | USER COMMENT |       1 |       1 | 1 updated news record id: 1 to news record id: 1 | 2011-11-23 10:55:16 |
+----+---------+------------+--------------+---------+---------+--------------------------------------------------+---------------------+