EXPD_TRACK_WBS 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 "WBS Tracking Information" 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_EXPD_TRACK_WBS TYPE EXPD_TRACK_WBS.
The EXPD_TRACK_WBS table consists of various fields, each holding specific information or linking keys about WBS Tracking Information data available in SAP. These include POSID (Work Breakdown Structure Element (WBS Element))... 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. .