Using Aliases to Rename Fields

Up until this point, when we want to include a field in our response, 0:00 we specify each field individually. 0:05 Now this is fine for experimenting, but when building an actual project, 0:08 there's a good chance we'll need to grab the same fields in multiple places. 0:13 Fortunately GraphQL makes this possible with a concept called fragments. 0:18 A fragment is simply a block of code 0:24 that specifies a group of fields that you want to include in your response. 0:27 To see how this works let's jump back in the Launchpad for an example. 0:32 For this example, we'll be using the movie by ID in point again, 0:36 aliased under movieOne and movieTwo. 0:41 Just like in the last video, we'll start with our query declaration. 0:44 Then we'll go ahead and write the first call the movieById, 0:49 which will be aliased under movieOne. 0:53 For this one, we'll use the movieId of movie_0, 0:58 then in our response we'll include the id, 1:04 title, tagline, and revenue fields. 1:09 Now let's go ahead and repeat the same thing for movieTwo. 1:14 Again, we've got the alias of movieTwo calling movieById. 1:18 The movieId we'll use for this one is movie_1. 1:25 And we'll go ahead and include those same fields again, 1:32 id, title, tagline and revenue. 1:37 Right now when we want to include the same fields for 1:41 each movie, we have to manually type those fields out inside of each end point call. 1:43 Now go ahead and run the query. 1:50 As expected it works fine, we have both of our movies, but 1:55 it was a little repetitive to type it all out. 1:58 You can probably see how this could get tedious pretty quickly. 2:02 This is exactly where fragments come in handy. 2:06 To define a new fragment we'll start with the fragment key word. 2:09 This fragment we'll call movie details. 2:14 We then need to tell GraphQL which type this fragment can be used on 2:20 using the on keyword followed by the Movie type. 2:25 After that, it's just like any other query. 2:31 Inside of the curly brackets we'll go ahead and 2:33 copy paste the fields we used from our query above. 2:37 Now let's modify those queries a bit. 2:52 Inside of the curly brackets, go ahead and delete those fields. 2:55 Now, instead of typing them all out, we can just include our new fragment. 3:04 To do this type in three dots followed by the fragment name, 3:09 which in this case is movieDetails. 3:13 I did the same thing for movieTwo. 3:19 Now go ahead and run that query. 3:24 As you can see, it works like a charm. 3:27 Using fragments when we need to retrieve the same information 3:30 can save us quite a bit of time and quite a bit of typing. 3:33