LBBIL_IT_REF 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 "Billing Item: Reference Data" 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_LBBIL_IT_REF TYPE LBBIL_IT_REF.
The LBBIL_IT_REF table consists of various fields, each holding specific information or linking keys about Billing Item: Reference Data data available in SAP. These include ITM_NUMBER (Item number of the SD document), REF_DOC (Document number of the reference document), REF_DOC_IT (Item number of the reference item), REF_DOC_TYPE (Activity or element category)... 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. .