COMT_PME_XREF 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 "Where-Used List of Attributes and Values" 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_COMT_PME_XREF TYPE COMT_PME_XREF.
The COMT_PME_XREF table consists of various fields, each holding specific information or linking keys about Where-Used List of Attributes and Values data available in SAP. These include SYMBOL_KEY (Data type of characteristic in symbol table)... 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. .