PROTB_N 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 "Log Structure Generation" 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_PROTB_N TYPE PROTB_N.
The PROTB_N table consists of various fields, each holding specific information or linking keys about Log Structure Generation data available in SAP. These include ICON (Icon with output length 2), STATUS (Character Length 11), MSGNO (Message number), TEXT (Text (length 132))... 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. .