felix@xxxxxxxxxxx writes: > ALTER TABLE A COLUMN AA ADD CONSTRAINT DELETE ON CASCADE You're missing the specification of the foreign key, not to mention spelling the CASCADE clause backwards. Try ALTER TABLE A ADD FOREIGN KEY(AA) REFERENCES B(BB) ON DELETE CASCADE > \h alter table seems to be missing any way to add a constraint to a > column. It's there, though you have to look to \h create table to see the alternatives for "table_constraint". regards, tom lane
