I am trying to add a new foreign key to an existing table where there is data in the column I am wanting to make a change to.
In dev, I have tried this where data does and does not exist. Where there is no data this works fine.
ALTER TABLE [rpt].ReportLessonCompetency WITH CHECK
ADD CONSTRAINT [FK_Grade_TraineeGrade_Id]
FOREIGN KEY (Grade) REFERENCES [rpt].TraineeGrade(Id)
Where there is data I get the following error
The ALTER TABLE statement conflicted with the FOREIGN KEY …