title: Teradata timestamp with time zone conversion to timestamp(0)
body: <p>I want to calculate two timestamps difference in Minutes. one with timestamp(0) startdttm and another one is timestamp(0) with time zone enddttm(converted from GMT to local time zone so its data types is timestamp(0) with time zone) subtraction is not working properly for some rows.
  So I want to convert enddttm to timestamp(0). Let me know how to convert timestamp(0) with time zone data type to timestamp(0). Timestamp(0) with time zone values and after conversion to timestamp(0) value should be same.</p>
  <p>employee_no        startdttm             enddttm_gmt           TIMEZONE     enddttm_local         (startdttm-endttm_local) Mins
  14697         3/12/2021 22:06:34    3/13/2021 06:04:30   Pacific  3/12/2021 22:04:30        -1438</p>
  <p>employee_no        startdttm             enddttm_gmt           TIMEZONE     enddttm_local         (startdttm-endttm_local)Mins
  14690   3/3/2021 14:18:07   3/3/2021 22:19:08       Pacific     3/3/2021 14:19:08        -1</p>