Query to mass subscribe users to their threads
 

After importing a tonne of threads, the existing users are not subscribe to the threads they have 'created' or 'posted' in.

Is it possible to execute a query that would subscribe users to their pre-existing threads?

Basically it would only be in one forum, and there's one user that I don't want to subscribe (a thousand threads were attributed to one 'default' user, and I don't want those to be subscribed).