Which db technology can I use for caching? [closed]

I'm developping a Client-Server application and a database to which multiple users will have to connect to. It's a .Net client windows application.

Some of the database queries will be performed so many times by each user and I'm thinking of creating a local cache at the client level that will be used to store frequently used static data in order to avoid increasing Oracle charge and keep database quering only for data not available in the cache or not up to date.

I though of using a standard database Access Database that will be stored at the client level or XML files but I was wondering if there is a better technology to perform this.

MongoDB is good in the sense that it can store very heterogenous data but it's very complex to handle for this need (Creating users, granting permissions...)

Does anyone have an idea please ? Thanks.