Jean-Christian Imbeault <jc(at)mega-bucks(dot)co(dot)jp> writes:
> $ psql TMP -c "update invoices set req_del_date3='today+8' where id > 10"
You can't do arithmetic inside a timestamp literal. The above actually
gets interpreted as "today" (meaning midnight) in timezone "+8", ie,
midnight 8 hours east of GMT.
regards, tom lane