SQL> -- FROM_TZ(x, time_zone): convert the TIMESTAMP x and time zone specified by time_zone to a TIMESTAMP WITH TIMEZONE
SQL>
SQL> SELECT FROM_TZ(TIMESTAMP '2005-05-13 07:15:31.1234', 'EST') FROM dual;
FROM_TZ(TIMESTAMP'2005-05-1307:15:31.1234','EST')
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13-MAY-05 07.15.31.123400000 AM EST
SQL>