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About UTC Data Conversion

The global time zone feature converts date-time data to and from UTC. When Siebel applications are deployed using UTC, some date-time fields store data as UTC data.

To support UTC conversion, applicable date-time field object definitions use the data type DTYPE_UTCDATETIME (instead of DTYPE_DATETIME), and applicable column object definitions use the physical type UTC Date Time (instead of Date Time). UTC conversion code is invoked by the Application Object Manager in user sessions where applicable, as described below.

NOTE:  To be subject to UTC conversion, custom date-time fields you create must be date-time fields only, not date-only or time-only fields, and must use the types mentioned above. See also Enabling Custom Date-time Fields and Columns for UTC.

There are some exceptions where date-time fields are not enabled for UTC. For more information, contact Siebel Technical Support.

Where the Universal Time Coordinated system preference is TRUE, UTC conversion in runtime operations occurs as described below:

• During runtime operation, date-time data that is entered by users (for example, appointment start or end times) is converted to UTC based on the time zone that is stored in the user's profile. If the Time Zone field in the user's profile is NULL, the time zone defined by the Default Time Zone system preference is used for this purpose instead. Daylight savings adjustments take effect according to the calendar date for the entered data.
• Date-time data that is displayed to users is converted from UTC based on the time zone that is stored in the user profile, including any daylight savings adjustments. If the Time Zone field in the user's profile is NULL, the time zone defined by the Default Time Zone system preference (with daylight savings adjustments) is used for this purpose instead.
• Date-time data that is entered into the database by the system (date-time stamp) is converted to UTC by the Application Object Manager before it is stored, based on the time zone of the application server machine.
• Siebel components that are not Object Manager-based (for example, Workflow Policies or Siebel EIM components on the Siebel Server) invoke UTC-specific database functions in order to handle date-time data consistently for UTC deployments.

See also About UTC System Preferences.