VBFAVB is a standard SAP Structure so does not store data like a database table does. It can be used to define the fields of other actual tables or to process "Reference Structure for XVBFA/YVBFA" Information within sap ABAP programs. This is done by declaring abap internal tables, work areas or database tables based on this Structure. These can then be used to store and process the required data appropriately. i.e. DATA: wa_VBFAVB TYPE VBFAVB.
The VBFAVB table consists of various fields, each holding specific information or linking keys about Reference Structure for XVBFA/YVBFA data available in SAP. These include MANDT (Client), VBELV (Preceding sales and distribution document), POSNV (Preceding item of an SD document), VBELN (Subsequent sales and distribution document)... 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. .