Eliminate Duplicate Records while Processing?

Hey all,

We're building out a simple application that does some calculations based on the data and keeps the record of all those results in a document DB(Azure Cosmos).

So since I am pulling all the data to make a conclusion based on the calculation(with the help of the Functions), for many of the times I am facing some duplicate records as exactly the same as the ones that I've inserted at the earlier run(since there won't be any changes on the data for every customer every day) e.g 6 out of 10 records are the same and the data volume is high.

So I'm looking out for ways to eliminate that duplicate records without raising Cosmos RU's to the sky. Any suggestions?