I make the following steps to generate reports in ASP pages:

1. Users selects tables they want to query.
2. User selects fileds from the selected tables to show on the reports.
3. We allow the user to query via input predefined fileds from the selected tables to produce the report.

this is to generate dynamic report from group of tables.
my question is : this tables have many relations that are unknown because the selected tables to generate the report are different form user to othre, any one know how could i determine the relations between tables from code.

I am not very sure as to which views but I think u can get it from the INFORMATION_SCHEMA

Regards
Ganesh

Not sure why you need to know the relations from code.
SQL Server will handle that for you.

You mean that when i write select statment without the relations between tables the sql server will handle it.

The relations are created using Enterprise manager or through SQL. Once the are there, you don't need to change them etc.

When you write a SQL SELECT statment, you still need to provide JOIN statements between tables.

   I think you may be confused between what a Relation is and Joining tables.