SQL problem with DDL and record id constraint

I am trying to add a field to a file defined in DDL using system I nav (opsnav) V7R1m0.

I navigate to the database and create the field. I uncheck NULLABLE which changes default to data type. This adds the field. But when I click ok on the table, I get an error, SQL State: 58004.

I reviewed the job log in opsnav and it looks like this:

Cause . . . . . : An access path was found that had the same attributes and key fields as the member being created. Member PROFREC file Q_AT000000 in library TEXASF shares the access path logically owned by member PROFREC file Q_AT000000 in library TEXASF. Because the access path was shared, it is possible that one or more of the following access path attributes were not used from the access path definition for member PROFREC:
-- Maintenance attribute (MAINT parameter).
-- Force attribute (FRCACCPTH parameter).
-- Recovery attribute (RECOVER parameter).
Use the DSPFD command to display the operational attributes of the access path.


Further tracing shows when we created the file in opsnav, we added a record id field as record identity column with unique value (which we are doing for all new files created with DDL) and go back and add it as a key contraint. But we did not realize the system generated a constraint name if we do not give it a name. Geez, we give it a column name and a system name, now we have to also give it a constraint name?

I have looked at some of the other new files we created and they also have a system generated constraint name.

This is the first time we have tried to add a field to a DDL defined file. We can add the field if we either use native SQL, or if we change the new field to nullable, then change it back. But changing to null and back gives us other problems.

Can someone explain the need for a unique constraint name and why that prevents me from adding a field?

---Dale