many to many relationship - whats best way to add/edit/delete

I have a many to many relationship

I can design the table 2 ways:

1) Category table (cat_id, cat_name, active) - cat_id as PK
CategoryReq (cat_id, req_name) - cat_id & req_name as PK

2)
CategoryReq (req_name, cat_name) - req_name & cat_name as PK

IfI design 1st way. Then when they want to add and delete from theCategoryRequest table, they would have to add to the category tablefirst. Then maybe build a list of checkboxes to select from. The one'sthey check insert into the CategoryRequest table.

Drawback ofthis is that they can't edit the list on the fly. Since it may be usedby other request (since cat_id CategoryReq is fk into Category table)

If I design it the 2nd way. Then they can edit, delete, add on the fly. But there won't be a master category list.

Which way is better?

Hi,

The design of the database strictly derives from the application requirements. But as a rule of thumb, you should generally create normalized tables to the third normal form in RDBMS theory. And then denormalize only if necessary. (Usually, the main reason for denormalization is performance improvement). Denormalization can be very harmful. Do it sparingly and only if you know what are you doing!