Assume p is a PERIOD(TIME(2)) column in table t with a value of PERIOD '(12:12:12.45, 13:12:12.67)' and the current session time zone displacement is INTERVAL -'08:00' HOUR TO MINUTE.
In the following example, a PERIOD(TIME(2)) column is cast as PERIOD(TIME(6) WITH TIME ZONE). The time portion is obtained from the source with trailing zeros added to the fractional seconds to make the precision 6 for the corresponding result element and both result time zone fields are set to the current session time zone displacement.
SELECT CAST(p AS PERIOD(TIME(6)WITH TIME ZONE)) FROM t;
The following is returned:
('12:12:12.450000-08:00', '13:12:12.670000-08:00')