Assume pts is a PERIOD(TIMESTAMP(2)) column in table t with a value of PERIOD '(2005-02-02 12:12:12.34, 2006-02-03 12:12:12.34)'.
In the following example, a PERIOD(TIMESTAMP(2)) column is cast as CHARACTER(52) using the CAST function.
SELECT CAST(pts AS CHARACTER(52)) FROM t;
The following is returned:
('2005-02-02 12:12:12.34', '2006-02-03 12:12:12.34')