CURRENT_TIMESTAMP returns the current timestamp when the request started. If CURRENT_TIMESTAMP is invoked more than once during the request, the same timestamp is returned. The timestamp returned does not change during the duration of the request.
If you specify CURRENT_TIMESTAMP without the AT clause or CURRENT_TIMESTAMP AT LOCAL, then the value returned depends on the setting of the DBS Control flag TimeDateWZControl as follows:
- If the TimeDateWZControl flag is enabled, CURRENT_TIMESTAMP returns a timestamp constructed from the session time and session time zone.
- If the TimeDateWZControl flag is disabled, CURRENT_TIMESTAMP returns a timestamp constructed from the time value local to the Teradata Database server and the session time zone.
CURRENT_TIMESTAMP returns a value that is adjusted to account for the start and end of daylight saving time (DST) only in the following cases:
- CURRENT_TIMESTAMP is specified with AT [TIME ZONE] time_zone_string, where time_zone_string follows different DST and standard time zone displacements.
- CURRENT_TIMESTAMP is specified with AT LOCAL or without an AT clause and the session time zone was defined with a time zone string that follows different DST and standard time zone displacements.
If CURRENT_TIMESTAMP is used in a stored procedure, the procedure must be recompiled whenever the DBS Control fields System TimeZone Hour or System TimeZone Minute are changed. Recompiling stored procedures is not necessary if a time zone string is set using the tdlocaledef utility.