Re: GDL2 and object inheritance.

[David Ayers]

Jim Fowler wrote:
> Greetings.
>
> First off, I'm extremely impressed with gdl2 and gsweb; I'm now using
> it to manage the student pages for a summer math camp.
>
> My database schema has tables that inherit from other tables; this
> seems to confuse GDL2.  In particular, the subclasses all share a
> sequence, but GDL2 doesn't seem know about this (although webobjects
> did, as it created the database).  I currently band-aid GDL2 by
> changing the code that decides what the sequences should be named
> (e.g., "address_seq" is replaced with "contact_seq" in the postgres
> adaptor), but I'm wondering if there is a more elegant solution to
> this?

Hello Jim,

Great to hear that you have GDL2 and GSWeb mostly working for you.  I 
haven't been able to check whether inheritance (either vertical, 
horizontal or one-table mapping) actually works in GDL2.  In fact I 
remember reading comments in the code that it probably doesn't.   But if 
the only issue you've run into so far is the primary key generation, 
then let's see what we can do.

http://developer.apple.com/documentation/LegacyTechnologies/WebObjects/WebObjects_4.5/System/Library/Frameworks/EOAccess.framework/ObjC_classic/Classes/EOSQLExpression.html#//apple_ref/occ/clm/EOSQLExpression/primaryKeySupportStatementsForEntityGroup:

documents that the sequences will be based on the externalName of the 
root entity via  -primaryKeyRootName and that /seems/ to be what is 
implemented used in EOAccess but...

Looking at the implementation of the method itself and doing a little 
testing on WO reveals that the correct inheritance handling has been 
commented out since the initial import of the sources.

Looking at the Postgres95AdaptorChannel, I see that doesn't ust the 
primaryKeyRootName of the entity either.

I'll blindly fix & commit without much testing as I really don't have 
much free time right now.  But if you still have an issue after this is 
committed, please feel free to file a bug report and if it turns out to 
be easily fixable, I'll try to squeeze it in.  (A small test case would 
be really great also!)

Cheers,
David