How to store state data in Ethereum blockchain

Question

Suppose I have an array of 200M users, now you wish to store more users (say 500M). Since each word of storage on the Ethereum blockchain requires 20K in gas fees.

Now, if I update a user's score and thus update the contract, do I need to store entire 500M words again??

Answer 1

You won't have to overwrite the whole array if you're not changing the order of records. You just have to pay gas for the data that you add or update.