Graeme Rocher (@graemerocher), Grails project lead about Grails support for Redis:
Redis is a key/value store which supports extremely fast read operations so it’s useful in a number of situations where caching solutions have been used, however since Redis supports complex data types like sets, lists and hashes you can also do some more advanced querying compared to other key/value stores. This makes it appropriate for a range of scenarios from sorting data, calculating statistics, queueing jobs or just basic caching.
As an example Redis’ set type allows you to store a unique set of values and easily return random entries or pop (remove) entries from a set. Implementing this type of functionality in a performant way on a relational database is typically much harder.
Even if compared with a caching solution, Redis will actually persist your data.
Original title and link for this post: Grails/GORM for Redis Interview (published on the NoSQL blog: myNoSQL)