3977 The Parent Key is not unique or not valid.
Explanation:
The referenced column(s) (Parent Key) specified in the referential constraint must either be a valid unique primary index (UPI) or a valid unique secondary index (USI) of the referenced table. Note that an UPI/USI could exist but in an invalid state and in which case this error will also be returned.
Generated By:
RES/OPT modules.
For Whom:
End User.
Remedy:
Use the Create Unique Index statement to define the referenced column(s) as unique in the referenced table.