Why in BICC PVO FscmTopModelAM.FinExtractAM.GlBiccExtractAM.BalanceExtractPVO PK can be null ?

Summary:

The default Primary Keys of BICC PVO FscmTopModelAM.FinExtractAM.GlBiccExtractAM.BalanceExtractPVO are BalanceActualFlag, BalanceCodeCombinationId, BalanceCurrencyCode, BalanceTranslatedFlag, BalanceEncumbranceTypeId, BalanceLedgerId, BalancePeriodName but BalanceTranslatedFlag and BalanceEncumbranceTypeId can be null.

Is-it normal that a Primary Key can be null ? According to our Data Team it's not normal and they don't want to manage the case of Primary key which can be null.

If we delete In the data store, BalanceTranslatedFlag and BalanceEncumbranceTypeId columns as Primary keys we will have issues :

Example :

Row 1 : BalanceLedgerId =10000, BalancePeriodName=25-10, BalanceCurrencyCode = EUR,   BalanceActualFlag='A', BalanceCodeCombinationId=10001,  BalanceTranslatedFlag=Null, BalanceEncumbranceTypeId = Null

Row 2 : BalanceLedgerId =10000, BalancePeriodName=25-10, BalanceCurrencyCode = EUR,   BalanceActualFlag='A', BalanceCodeCombinationId=10001,  BalanceTranslatedFlag=Y, BalanceEncumbranceTypeId = Null