>I agree Paul's view, it is not good on modify structre at run-time!

Did I ever say something like this? No.

>1. You need to Exclusive right on table, it is NOT flexible for
>multi-user

That's not true. Keeping a template structure and creating a temp table from it doesn't require exclusive access. And it is flexible for multi-user because each user will have his/her own temp table.

>2. In case your application crash during reformat the table, you lose ur table!

You may lose only the temp table. So, no problem at all.

Besides all this, Pierre's final solution is better anyway. :)

Vlad