Realtime datasource issues.

How are you guys ?. I have following question.

1.) For instance datasource is from SAP system to be replicated to SAP BW., Datasource contains fields of SAP

Transaction system tables. Datasource has information of fields from different SAP tables, my question

is if datasource has different tables information with basis on what with primary keys they possess or not by

datasource to maintain uniqueness of data and where can i find table names of datasource fields.