R2DBC: Reactive Programming With Spring, Part 4 The fourth part of the blog series contains an introduction to Spring Data R2DBC. by Join the DZone community and get the full member experience.Join For Free This is part 4 of my blog series on reactive programming, which will give an introduction to R2DBC and describe how we can use Spring Data R2DBC to create a fully reactive application. 1. What is R2DBC? If you are not already familiar with reactive programming and Reactive Streams, I recommend you to first read my introduction on reactive programming which describes the motivation behind this programming paradigm.