The Area being Modelled is :-
A Data Model for Document Template Management

The Requirements have been defined in a question to the Database Answers Web Site.

Subject: document template managment

Question: I need to manage document template.
Users use our client program write their documents.
Every document must use a template,that is ,user must pick up a template from server
before their works.

The biggest problem is the templates are maintained by a department and is changed every month.

We need store all the templates' history in the database.

When a template is changed, documents having applying this template should be changed also.

The history of documents also should be stored in the database (something like svn. User can
compare the history, view the history).

The most crazy things is that the document cotains paragraphs and tables.

Paragraphs having specific means will be parsed by our program and stored in different table, and
so dose the tables in documents, but difference between paragraph and table in document is that
colums of table can be added or removed by user.

So, i have 2 big problem
1. how do i manage the history of template and documents, and the relation between the documents and templates ?
2. the tables in documents will be parsed and stored in database. the columns of the table can be changed by user,
   so, how do i desgin the table in database.

Performance may be a big issue

Thanks a lot
Barry has defined the 'Things of Interest' as follows :-
A.1 Documents
A.2 Templates
A.3 Others to be determined

The Business Rules are as follows :-
B.1 To be determined