Modelling Dimension relations over time

[menon_manish]

Hi,

We are planning to model a star schema based data warehouse with the following challenges:
1- The fact table is dimensioned across sales rep postion (a logical designation), geography, product, sales and atime
2- The sales reps have different positions over time, work in different geogs and with different products
3- Each of the dimensions have a hierarchy (Sales Rep Name-> manager name etc.), position hierarchy (Sales rep position name -> manager position name etc.) and product and geography also

Given this, do we put the sales rep key in the fact table and capture the dimensional relations of sales rep with Geog, Prod etc using factless fact? Or do we put all the keys in the fact table and lose the ability to navigate dimensions solely but only through the fact

THanks
Manish