Several good tools exist for storing, serving, and managing relational data; Redis is not one of them. As Redis requires a query-based modeling approach, reading relational data may require multiple operations and potentially application-side joins. Additionally, Redis is not an ACID-compliant database, which can further complicate write operations if the relational-like behavior is expected.
ACID is an acronym for Atomicity, Consistency, Integrity, and Durability. Typically, only relational databases are considered to be ACID-compliant databases.