You can add a new index colum in each table of course that you must manage the relation type between they, and in the transformation app you can use a mapping funtion to relation all tables.
Id_Segmento (new column)
ApplyMap('Segmento_Map', [0DIVISION]) as Id_Segmento,
In Qlik you can manage the ETL proccess with an app for each part of the proccess... this way to work help you to have control over the total proccess, is just a way to work. the idea is the next:
1- Exraction app.- Extract the data from the source database and store the result in an qvd file.
2- Trasformation appa - Make all the trasformation over the data to make business sense information, and also store de results in a qvd.
3- And finaly you have all the neccesary to make your dashboard.
As i told you, you can do all these in a sigle app, but you get more control if do in this way.
I hope this help you