BPBK is a standard SAP Table which is used to store Doc.Header Controlling Obj. data in SAP systems, such as SAP R/3, S/4HANA, depending on the version and release level.
The BPBK table consists of various fields, each holding specific information or linking keys about Doc.Header Controlling Obj. data available in SAP. These include BELNR (Document number from budget allocation & structure planning), GJAHR (Fiscal Year), VORGA (Budget Type Budgeting/Planning), CPUDT (Date Document Was Created)... See below for full list along with technical details, documentation, text table, check tables, foreign key relationships, conversion routines, relevant tcodes and example ABAP select code etc. .