Dmitry Yemanov wrote:

>
> I recall Ann was fixing some bugs for a customer who used extra fields
> added to system tables...
>

I'd certainly favor disallow alter column or drop column on system
tables. However, there's a good chance you'll break some
applications if you disallow add column on system tables.

Yes, users have added columns to system tables and run into problems -
specifically, gbak doesn't restore the user defined columns because
it creates system tables from a template. I had a prototype that
checked for new system table columns, backed up them and their
contents, and restored them. The customer went with a script he ran
before backup and after restore.

Frankly, having separate tables with additional material is a better
way to go.



Cheers,


Ann