Re: question about the design consideration for system catalogs

"Tom Lane" <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrotes:
> "Tao Ma" <feng_eden(at)163(dot)com> writes:
>> But if I wanna check the parameter informations, it's a little hard to
>> read. If I wanna write a program to re-construct the procedure source
>> code, it is not convenience to access the parameter informations from
>> the front-end. What cons are there If store the procedure and its
>> parameters in different tables(e.g. pg_attribute and pg_attrdef)?
>
> Loss of backwards compatibility, for one thing. We're not going to
> redesign those catalogs just because somebody thinks some other layout
> would be more convenient for one purpose --- it would break a lot of
> code for little gain.
>
Thank you. Actually, I don't want to change anything. I am curious
why we use this form, such as it is easy to access the informations
internally, and so on. Or this form is jsut historical reasons, we
follow the original patterns. I know the system catalogs is very
important and critical to the DBMS. So pls don't mind me and my poor
questions.

TIA