Added documentation for aliases (#908)

doc/10_GraphQL/04_Query/06_Operators.md

@@ -6,7 +6,8 @@ Operators allow to modify and transform the data before it is delivered to the e
 
 #### Alias
 
-Simply gives the child node a different name.
+Simply gives the child node a different name. 
+See also [Using Aliases](./11_Using_Aliases.md) for more information on how to use aliases.
 
 #### Date Formatter
 

doc/10_GraphQL/04_Query/11_Using_Aliases.md

@@ -0,0 +1,37 @@
+# Using Aliases
+
+Aliases are used to rename the result of a field. 
+This is useful when you want to return multiple fields with the same name.
+
+There are two ways to use aliases:
+
+## Alias Operator
+
+See [06_Operators.md](06_Operators.md) for more information.
+
+## Alias in the Query
+
+Get a `Car` with id 82 and return the number of doors.
+The first value is the alias, the second value is the field name.
+
+#### Request
+```graphql
+{
+  getCar(id: 82) {  
+  doors: numberOfDoors
+  }
+}
+```
+
+#### Response
+```json
+{
+    "data": {
+        "getCar": {
+            "doors": 2
+        }
+    }
+}
+```
+
+