Implementation of Date
Date is implemented in SAP as CHARACTER*8 with implicit conversion exits.
Elementary data type = D Internal length = output length = 8
System data type = DATS Internal length = 8 output length = 10
Both the data types has no restriction on the actual value being stored but conversion-exists always treats the date in format 'YYYYMMDD'.
Most of the times both type 'D' and 'DATS' behaves similarly except when they are output without any overriding additions. In such cases a 'DATS' type variable will be output with separators as specified in the "Date Format Settings" while a type 'd' variable will be output without separators.
Date Output Formats
Settings used to format the date can be supplied in 3 ways,
1. USER setting - Transaction SU3
a. USER setting is the default setting used by SAP for output
2. LOCALE/COUNTRY setting - Transaction OY01
a. Use command SET COUNTRY Returns the timestamp in short or long form. The short form contains the current date and time; the long form also contains seven decimal places for fractions of a second, making the timestamp accurate to within 100 nanoseconds.
Time Zone
the world is divided into 24 time zones spaced at intervals of 15 degrees in longitude. The zones start at 0 with Greenwich. Within each time zone, the hour and minute of the day is defined to be the same. Time zones are usually specified by the number of hours they differ from GMT
TTZCU Customizing time zones table.
DST : Daylight Saving Time gives us the opportunity to enjoy sunny summer evenings by moving our clocks an hour forward in the spring.
Note :
Simple write statement is not going to put Timestamp in the desired output format. One has to specify a TIME ZONE for output formatting.
Transaction STZBD is used can be to maintain time zones .
1. TTZZ : Time zones
2. TTZR : Time zone rules
3. TTZD : Summer time rules (Daylight saving).
4. TTZDF : Summer time rules (fixed annual dates)
5. TTZDV : Summer time rules (variable dates)
System Variables
1. SY-TZONE Date and time, time difference from Greenwich Mean Time.
2. SY-DATUM Date and time, current (application server) date.
3. SY-UZEIT Date and time, current application server time.
4. SY-ZONLO Date and time, time zone of user.
5. SY-DATLO Date and time, local date of user.
6. SY-TIMLO Date and time, local time for user.
Time Stamp Conversion
CONVERT TIME STAMP tst
TIME ZONE tz
INTO DATE d
TIME t .
CONVERT DATE d
TIME t
INTO TIME STAMP tst
TIME ZONE tz.
The time stamp tst is always UTC time while d and t are always based on the time zone tz.The system always converts using the difference between the timezone tz and UTC time.
This implies that if you want to convert between non-UTC time zones then you can use the above statements in conjunction, First convert date & time in time zone 1 into UTC time stamp and then convert the UTC time stamp into date & time in time zone 2.
