# RedisGears readers A reader extracts data from the database and creates records. The [`GearsBuilder.CreateGearsBuilder(reader)`](http://redis.io/docs/latest/operate/oss_and_stack/stack-with-enterprise/gears-v1/jvm/classes/gearsbuilder/creategearsbuilder) function takes a reader as a parameter and passes the generated records through a pipeline of RedisGears functions. ## Classes