Re: 6.0 Schema

Mike Alder writes: > With the release of the new OnLine Informix engine ver6.0, >giving us the power to perform massive, cascading deletes and updates at >our finger tips , a few new questions concerning the database schema >come to mind. > > - Are we assigning the modeling aspects of the PK and FK > physically to columns when we build our tables. If not > how will they be identified, by name? You specify the primary and foreign keys and their relationships either when you create the table or when you alter its referential constraints. You can assign them a name, mostly for the convenience of dropping them later. Alternatively, the server will supply a name if you do not. > - Can this cascading traverse databases,platforms,stars..? No, since referential constraints cannot span databases, the cascading delete can only work on tables within teh same database. > - Are there guards that could be set against these types of > deletions or updates? (besides database,table ownership) If so, > are there different levels of guards that could be > implemented? No, if a user has persmissions to delete from the tables, there is no way to prevent them from cascading a delete. However, if they do not have delete permission for all tables involved in the cascade (there can be multiple levels, as a cascaded delete can generate another), then the entire delete (including that of the parent) will fail. > - Does informix have any intention of coming out with "any" > enhanced modeling tools that could be used along > with the engine? I'm not familiar with the modeling tools out there. There are various monitoring tools in the works. There is the DBA tool currently available with Viewpoint that can create and maintain a virtual view of the database (shielding end users from the relational model). I'm not sure what third parties are working on in this arena. Dave -- Disclaimer: These opinions are not those of Informix Software, Inc. ************************************************************************** "I look back with some satisfaction on what an idiot I was when I was 25, but when I do that, I'm assuming I'm no longer an idiot." - Andy Rooney