Add Grab Multiple Values From A Reference as a GROQ TIL

groq/grab-multiple-values-from-a-reference.md

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+# Grab Multiple Values From A Reference
+
+Let's say we have an `author` with some attributes including a reference to a
+`person` which contains more data about the person. Here is one way to write a
+query to access that data.
+
+```groq
+*[_type == 'author' && slug.current == 'donna-tartt']{
+  website,
+  'firstName': person->firstName,
+  'lastName': person->lastName,
+  'age': person->age
+}
+```
+
+Here is another way to write this query that doesn't do three separate accesses
+on the `person` reference.
+
+```groq
+*[_type == 'author' && slug.current == 'donna-tartt']{
+  website,
+  person-> {
+    'firstName': firstName,
+    'lastName': lastName,
+    'age': age
+  }
+}
+```
+
+This isn't quite right though because it leaves the three reference values
+nested under `person`. We can get back to the original shape of our query by
+flattening the `person` object using familiar looking spread syntax (`...`).
+
+```groq
+*[_type == 'author' && slug.current == 'donna-tartt']{
+  website,
+  ...person-> {
+    'firstName': firstName,
+    'lastName': lastName,
+    'age': age
+  }
+}
+```