You can customize the default mapping data for the Islamic calendar.
Authorization Object | Field | Value | Description |
---|---|---|---|
S_ADMI_FCD |
S_ADMI_FCD |
SCP1 | Set character sets, languages, and character conversions. |
The Islamic calendar is strictly lunar. Therefore, an Islamic year of twelve lunar months does not correspond to the solar year used by most other calendar systems, including the Gregorian calendar. An Islamic year is, on average, about 354 days long, so each successive Islamic year starts about 11 days earlier in the corresponding Gregorian year. For example, the beginning of the Islamic year 1436 corresponds approximately to the Gregorian date 25 October 2014 and the beginning of the Islamic year 1437 corresponds approximately to the Gregorian date 15 October 2015. Each Islamic year has 12 months with either 29 or 30 days per month.
The mapping information for the Islamic and Gregorian calendars is stored in the database table TISLCAL. The beginning date of each Islamic month is defined by its corresponding Gregorian date in the table. As a default, the table contains date information which is calculated from a formula, the Tabular Islamic Calendar. The months are determined by arithmetic rules rather than by observation of the visibility of the new moon. The calculation is based on a 30-year lunar cycle where the length of the lunar months is defined alternatingly as 29 or 30 days. Every two or three years, an extra day is added at the end of the year to keep up with the phase of the moon. A leap day is added 11 times in a 30-year cycle.
You can change the default entries calculated according to this algorithm by adding a customized Gregorian date for table TISLCAL.