GRFN_S_API_EO 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 "Enterprise Object" 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_GRFN_S_API_EO TYPE GRFN_S_API_EO.
The GRFN_S_API_EO table consists of various fields, each holding specific information or linking keys about Enterprise Object data available in SAP. These include VALIDFROM (Start Date), VALIDTO (End Date), DESCR (Object Name), LTEXT (Object Description)... 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. .