Jesper Krogh <jesper(at)krogh(dot)cc> writes:
> The tables are running a "home-made" timetravelling feature where a
> contraint on the table implements the foreing keys on the table.
You mean you have check constraints that do selects on other tables?
You have just found out (one reason) why that's a bad idea.
> How can I instruct pg_dumpall to turn off these constriants during
> dump/restore?
Drop the constraints in the source database.
regards, tom lane