If you create a new record when a previous record already exists, the system reacts in one of the following ways: it delimits, extends, splits, or deletes the record. The system reaction depends upon the time constraint. The time constraint is a characteristic of infotypes and subtypes. In the master data, we differentiate between three different time constraints (1, 2, and 3). Besides, there are also time constraints A, B, T and Z.
Infotypes or subtypes with time constraint 1 must be unique meaning that only one valid record can exist for any given time period. There can be no gaps between records. When you add a new record to an infotype with time constraint 1, the system delimits the overlapping infotype record on the key date and adds the new record. This happens with the Basic Pay infotype (0008), for example. If you delete a record that must exist at all times, the previous record is automatically extended. There can be no gaps between records.
Infotypes or subtypes with time constraint 2 can only have at most one record for a given time period. There can be gaps between records. If records overlap, the system adapts the previous record accordingly by deleting, dividing, or delimiting it. An example of an infotype with time constraint 2 is the subtype Spouse (1) in the Family/Related Person infotype (0021).
Infotypes or subtypes with time constraint 3 can have gaps between records or overlapping records. If records overlap, the system does not react at all. Examples of infotypes with this time constraint are Monitoring of Dates (0019) and Objects on Loan (0040).
Infotypes with time constraint A may have only one record for ever i.e., from 1.1.1800 to 12.31.9999. Splitting or deletion is not permitted. Example, Payroll status infotype (0003). This infotype would be automatically maintained by the system when a person is hired.
Infotype with time constraint B are similar to infotypes with time constraint A. But, these infotypes may be deleted. Example, Applicant Personnel Number infotype used to maintain applicant’s personnel number.
When the time constraint varies according to the subtype of an infotype, then the infotype is assigned time constraint T. Example, Family member details infotype (0021) with Spouse and Child subtypes.
Infotype 0021—-Time constraint T
Spouse subtype—Time constraint 2
Child subtype—Time constraint 3
All Time Management Infotypes are given the time constraint Z.