Simplify Collection Management with ngrx Entity in Angular

Data manipulation on collections can be expensive because it is usually necessary to iterate over the collection at least once to perform any kind of update or selection to it. A common pattern for avoiding expensive iterations is to break a collection into a key-value store that allows for instantaneous lookup of value provided you have the key. We could handle this data transformation ourselves but ngrx entity was created to do all the heavy lifting for us. In this lesson, we will see how to update how we define our feature state to use EntityState, create an EntityAdapter, define our initial state using our adapter and most importantly, how to leverage the convenience methods that the adapter gives us in our reducer. We will also examine how ngrx entity changes the shape of our state by splitting our collection into ids and entities and how to update our feature selector to work with it.