In my opinion, you need to create an 'user-activity' database. It's simple to do, because it should at least have only one table, like this:
ActivityID - INT (IDENTITY)<br />
UserID - INT -> user name, id or any other unique value<br />
DatabaseID -> database name, id or any other unique value<br />
TableId -> table name, id or any other unique value<br />
UserActivity - VARCHAR(255) -> description of user activity<br />
ActivityTime - DateTime<br />
The number of tables or fields depends on your criteria.
Before you save data, save user 'activity'.