UPC_YS_STEPS 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 "Characteristic Relationships: Steps" 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_UPC_YS_STEPS TYPE UPC_YS_STEPS.
The UPC_YS_STEPS table consists of various fields, each holding specific information or linking keys about Characteristic Relationships: Steps data available in SAP. These include STEP (Number of the Characteristic Relationship), MTYPE (Type of Characteristic Relationship), TO_SOURCE (), TO_TARGET ()... 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. .