First of all, thanks for your answer.
I'm sorry, I must be more clear about this issue.
Previously, I wrote "three" Producttype, but really I don't have a fixed number. The product type column number is random, it depending on sales distribution.
Practically, I don't know which Product type will be loaded
Hope this is more clear
Welcome to qlikview world!!
1) make a Pivot Table
2) Customer as first dimention
3) Product as second dimention
4) Sum(Sales) as Expression
5) Go to Presentation. In Dimentions and Expressions (upper left corner) you will see all the dimentions and expressions you have. When you select one dimention, you can click on "Show partial sums". In your case, if you want to get the total of each customer, click the "Show partial sums" for the Product dimention. If you want to see the total for each Product too, click on the same for Customer.
6) click ok Ok for make the table
7) click on the Product column field, and drop it to the left, until the blue flag cames horizontal.
8) enjoy you table!!
I recomend that you "play" with the options, for understanding them.