SAP Business Information Warehouse (BW)

Internal key of type INT4 that you use for master data for master data-bearing characteristics, especially for hierarchy nodes and for characteristic names.

Master data IDs (SIDs) and characteristic values are stored in master data tables (SID tables).

Information about time-independent or time-dependent master data, which is stored in a P table or a Q table, is saved again in an X or Y table, using SIDs instead of characteristic values.