Jeff Eckermann <jeckermann(at)verio(dot)net> writes:
> I thought (based on recent posts) that this use of RETURN is allowed, but
> when trying an insert to report_table, I get the following error:
> ERROR: control reaches end of trigger procedure without RETURN
Looks to me like you didn't cover the case where billing_frequency is
not any of the values you tested for. Maybe you just want to raise
an error in that case...
regards, tom lane