I need your suggestion for applying Federation in SQL AZURE. In one my recent project I already have an Azure database. In this project I have a big list of customers and each customer has another big set of registered users (more than 25000 because it's a medical system).
For that our job is to create a federation for each customer. So there customer data is stored in master DB and registered user data under each customer can be stored in a separate federation member.
Here my problem is how can I design a federation key because if I use customer Id as federation key then all the user in the first federation member should have same key. So it's not possible. If you have any idea then share that with me please
How can I solve this problem? Please help me.