FRMLS_ITEM_COMP 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 "RMS-FRM: Data of a Composition Item" 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_FRMLS_ITEM_COMP TYPE FRMLS_ITEM_COMP.
The FRMLS_ITEM_COMP table consists of various fields, each holding specific information or linking keys about RMS-FRM: Data of a Composition Item data available in SAP. These include POSNR (Number of a Material or Substance Item), ROLE (Component Type (Material, Substance, or Stream Item)), STD_ALT_FLG (Standard Item), FLG_ALT_EXIST (Alternative Items Exist)... 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. .