Prevent two users from editing the same data

Question

I have seen a feature in different web applications including Wordpress (not sure?) that warns a user if he/she opens an article/post/page/whatever from the database, while

Answer 1

Sounds like it will work fine. If you want to denormalize this and remove the extra Events table, just add a UserId and Timestamp field to the Articles table, as that is all you really need.

You can easily check if the UserId doesn't match and if the Timestamp is less than 100 seconds old, then show the message.

This way, you won't have to do any deletions on a separate table.