Bill,

Must be misunderstanding. I didn't say that CLASS_PK is the primary key in the PARTS table. It is the primary key in the PART_CLASS table (new table). (the PARTS table does have the primary key which is not relevant to this).


>I must be missing something Dimity.
>
>Why is class_pk in the parts table a primary key?
>
>I'd expect the part number or something like to be the PK in that table.
>
>
>>Hi,
>>
>>I must be missing something simple. When I try to set the foreign key constraint, it fails. Here is the description:
>>1. I added new table PART_CLASS with primary column CLASS_PK (Int), Identity.
>>2. I added to PARTS table a column CLASS_PK (int), default 0
>>
>>I want to be sure that when/if the row/record in PART_CLASS is deleted, all referenced rows in PARTS set the value in columnd CLASS_PK to default (0).
>>
>>I think the constraint, when I set it up in SSMS, fails because table PARTS has many records and all of them have value 0 in the column CLASS_PK. But table PART_CLASS has no records. So SQL Server does not find a record in PART_CLASS of CLASS_PK value 0.
>>
>>How do you deal with this? TIA.