17.10 - Usage Notes - Advanced SQL Engine - Teradata Database

Teradata Vantageā„¢ - SQL Functions, Expressions, and Predicates

Product
Advanced SQL Engine
Teradata Database
Release Number
17.10
Published
July 2021
Language
English (United States)
Last Update
2021-07-28
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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 Vantage 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.