FQL vs Graphql

I am not sure which one to choose? both is comfortable to me…but in my opinion, gql will produce redundancy queries on database.

You can indeed optimize FQL queries more than GQL. I’m not certain what you mean with redundant, one GraphQL query results in one FQL query (e.g. no N+1 problem How Fauna's GraphQL API Solves the n+1 Problem). The amount of reads of that one query however can be more optimized with FQL. You might be interested in this forum post:
What are pros and cons between FQL and GraphQL?