What is the use of inverted date format

Question

In table TCURR - Exchange rates, the field GDATU - Date As of Which the Exchange Rate Is Effective is stored as an inverted date. So 01/01/2008 is actually stored as 79919898.
What is the use of inverted dates. Why does SAP use them. Why not just use normal date format? If I want the latest record from the table, instead of sorting by descending, I actually have to sort by ascending because the date is stored in inverted format.

Answer 1

Hi,
Inverted date is a old concept which helps in soring the dates sometimes. but now ASCENDING and DESCENDING sorting is more easy and quick. Check this application help. maybe useful for you
1. CONVERT DATE f1 INTO INVERTED-DATE f2.
2. CONVERT INVERTED-DATE f1 INTO DATE f2.
Effect
Calculates the nine's complement of the internal date format (YYYYMMDD - for more information about internal display, meaning and initial values of types, see TYPES) and places it in the field f2. For example, 19950511 becomes 80049488 and 80049488 becomes 19950511.
In the inverse date format, the most recent date has the numerically smallest value. You can make use of this effect when sorting dates.
Note
The technique of manipulating the sort sequence of dates by inverting the internal date format is now rarely used. You can sort internal tables in order of ascending or descending date values much more efficiently using the ... ASCENDING or ... DESCENDING additions to the SORT statement.
Example
DATA DATE_INV LIKE SY-DATUM.
CONVERT DATE SY-DATUM INTO INVERTED-DATE DATE_INV.
Suppose, for example, SY-DATUM contains the date 11.05.1995 in its internal format 19950511. After execution of the CONVERT statement, DATE_INV would contain the internal format 80049488.
//Kothand