oracle: Add constraint that checks column for existing value

Question

I'd like to add a constraint to a column that prevents a new row insertion if the value to be added to that column doesn't exist already. I've been at it for a while, this isn't my current code but I wanted it to be clear what I'm trying to accomplish.

ALTER TABLE emps
 ADD CONSTRAINT department_id_ck 
 WHERE department_id = 10 | 20 | 50 | 60 | 80 | 90 | 110; 

Any help is greatly appreciated.

Answer 1

After a little bit of playing this is the statement that I was looking for...

ALTER TABLE emps
 ADD CONSTRAINT department_id_ck CHECK (department_id IN (10, 20, 50, 60, 80, 90, 110));