CMS_STR_CAG_DATA_IN_BUF 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 "Structure to represent data that is available in the buffer" 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_CMS_STR_CAG_DATA_IN_BUF TYPE CMS_STR_CAG_DATA_IN_BUF.
The CMS_STR_CAG_DATA_IN_BUF table consists of various fields, each holding specific information or linking keys about Structure to represent data that is available in the buffer data available in SAP. These include CAG_GUID (GUID for Table CMS_CAG), FLG_BUPA (Flag: Indicates that the BP data needs to be fetched), FLG_DOC (Flag: Indicates that document data needs to be fetched), FLG_PORTIONS (Flag: Indicates that the Protions need to be fetched)... 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. .