Have a question on approach to take for best way to query the data which is in following format
Customer ID : 12345
Product ID : ABC
We have document as modeled above in CB with a distinct customer count of around 2 million.
Distinct product count that we have i.e. Product ID mentioned above in the document is around 3K
Requirement that we have is to get list of all customers who have a certain product ID,
For this requirement is it advisable to create an index on Product ID attribute? Reason that i ask this question is as mentioned above it is only 3K disctinct products that we have which are taken by these 2 million customers.
What is an optimal way to approach this requirement