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Rules for Time Zones

The conversion of the UTC reference time to the local date and the local time zone is based on a set of rules stored in AS ABAP system tables. The names of all associated tables start with TTZ. The following database tables, whose content you can maintain using transaction STZBD, are relevant for time zones:

A correct set of rules must contain all rules specified in TTZZ for the time difference between time zones and the UTC reference time in TTZR and all rules specified for summer time in TTZD. If the time difference between summer time and winter time in TTZD is not equal to 0, the respective summer time rule must be included in at least one of the tables TTZDF or TTZDV. While TTZDF contains fixed dates for the switch, the date in TTZDV is variable, because a day in a particular week of a month is specified. The system always checks TTZDF first for the summer time rule and then TTZDV.

Notes for Summer Time

If a time zone specifies a summer time rule with a summer time difference not equal to 0, note the following: