Introduction to the Data Layer

The data layer

This chapter will continue looking at the D for data part of "Do fun things with big, loud worker-bees.” We’ll use the Elixir datatypes we saw in the previous chapter to roll up data structures. Elixir is a functional programming language, and that concept will significantly impact how we represent data. In functional programming, functions can’t update data in place. Instead, they must create new copies that transform data step by step. When our data structures are wrong, our code must compensate and will, in turn, not only look awkward but will also feel wrong. The following figure shows that our data layer often serves as the foundation: