Understanding Time Zones
PeopleSoft applications store times based on a system-wide base time zone and support the display of times relative to a user’s local time zone or relative to the time zone in which a transaction is entered (called a specified time zone).
For example, if the base time zone is U.S. Pacific time (PST), a time entered as 10 a.m. in U.S. eastern time (EST) is stored as 7 a.m. because of the time difference between the two locations. This allows for easy comparison and manipulation of times so that PeopleCode developers do not have to worry about time zone differences. Additionally, all batch processes, such as structured query reports and COBOL, operate in the base time zone of the system.
However, although the time is stored as 7 a.m., it can still appear to the user as 10 a.m. EST, or as the appropriate time for any time zone that you choose. You can also set up the system to enable users to choose the time zone for specific time or datetime displays.
To support display in alternate time zones, the PeopleSoft system delivers an initial global list of time zones, including information about daylight saving time (DST) observances. When a time zone begins or ends in daylight saving time, both the description of the zone and the times that are associated with that zone are adjusted to reflect the change. This approach ensures chronological consistency throughout an organization’s geographically dispersed locations, while allowing for flexibility in how users see times.
Note: If your base time zone is one that observes Daylight Saving Time (DST) , you will get an ambiguous time listed during the changeover hour in the Fall. For example, in US Pacific Time, there are two 1:30 AM, first in PDT and then in PST. Since 1:30 AM PDT or PST is not marked in the timestamp object, if transactions during this time rely on that difference, it should be marked separately whether DST is in effect or not. Choosing a base time zone that does not observe DST, such as Universal Coordinated Time (UTC), would eliminate this ambiguity especially for the customers with multiple branches with different timezones.
Base Time Zone Details
This time zone is used for display when no other time zone is specified. The base time zone must match the time zone in which the database server is operating, specifically the time zone to which the meta-SQL %CurrentDateTime token returns. For example, in an Oracle database, the base time zone is the time zone in which the SYSDATE system variable is returned. You must enter this time zone on the PeopleTools Options page for your system to function correctly.
The base time zone is also used for the following:
All effective-date processing.
Rows become effective when midnight passes on the effective date according to the base time zone of the system.
Internal processing in PeopleCode and all batch processes.
Display on pages and in reports, if no other time zone information is specified or available.
Specified Time Zone Details
Specified time zones are useful for applications where users must see the same time and time zone as those who enter transactions, such as in call processing systems. To implement a specified time zone field, your record must contain a time zone control field.