feat: document enabled feature flag, and usage in secondary index section of data modeling page (aws-amplify#4801)

Author: alharris-at

src/components/FeatureFlags/feature-flags.json

@@ -256,18 +256,18 @@
         "description": "Changes the behaviour of @index directive to auto-generate Queries for indexes if no 'queryField' is provided.",
         "type": "Feature",
         "valueType": "Boolean",
-        "versionAdded": "8.5.x",
+        "versionAdded": "8.5.0",
         "values": [
           {
             "value": "true",
             "description": "An empty 'queryField' will cause a Query to be auto-generated. Explicit null value will disable this functionality",
-            "defaultNewProject": false,
+            "defaultNewProject": true,
             "defaultExistingProject": false
           },
           {
             "value": "false",
             "description": "A Query will only be created if the 'queryField' is explicitly set",
-            "defaultNewProject": true,
+            "defaultNewProject": false,
             "defaultExistingProject": true
           }
         ]

src/pages/cli/graphql/data-modeling.mdx

@@ -87,11 +87,36 @@ type Customer @model {
   id: ID!
   name: String!
   phoneNumber: String
-  accountRepresentativeID: ID! @index(name: "byRepresentative", queryField: "customerByRepresentative")
+  accountRepresentativeID: ID! @index
+}
+```
+
+The example client query below allows you to query for "Customer" records based on their `accountRepresentativeID`:
+
+```graphql
+query QueryCustomersForAccountRepresentative($accountRepresentativeID: ID!) {
+  customersByAccountRepresentativeID(accountRepresentativeID: $accountRepresentativeID) {
+    customers {
+      items {
+        id
+        name
+        phoneNumber
+      }
+    }
+  }
 }
 ```
 
-The example client query below allows you to query for "Customer" based on their `accountRepresentativeID`:
+You can also overwrite the `queryField` or `name` to customize the GraphQL query name, or secondary index name respectively:
+
+```graphql
+type Customer @model {
+  id: ID!
+  name: String!
+  phoneNumber: String
+  accountRepresentativeID: ID! @index(name: "byRepresentative", queryField: "customerByRepresentative")
+}
+```
 
 ```graphql
 query QueryCustomersForAccountRepresentative($representativeId: ID!) {
@@ -114,15 +139,14 @@ type Customer @model @auth(rules: [{ allow: public }]) {
   id: ID!
   name: String! @index(name: "byNameAndPhoneNumber", sortKeyFields: ["phoneNumber"], queryField: "customerByNameAndPhone")
   phoneNumber: String
-  accountRepresentativeID: ID! @index(name: "byRepresentative", queryField: "customerByRepresentative")
-}
+  accountRepresentativeID: ID! @index
 ```
 
 The example client query below allows you to query for "Customer" based on their `name` and filter based on `phoneNumber`:
 
 ```graphql
 query MyQuery {
-  customerByNameAndPhone(phoneNumber: {beginsWith: "+1"}, name: "Rene") {
+  customerByNameAndPhone(phoneNumber: { beginsWith: "+1" }, name: "Rene") {
     items {
       id
       name
@@ -594,6 +618,19 @@ type Address @model {
 }
 ```
 
+### Generate a secondary index without a GraphQL query
+
+Because query creation against a secondary index is automatic, if you wish to define a secondary index that does not have a corresponding query in your API, set the `queryField` parameter to `null`.
+
+```graphql
+type Customer @model {
+  id: ID!
+  name: String!
+  phoneNumber: String
+  accountRepresentativeID: ID! @index(queryField: null)
+}
+```
+
 ## How it works
 The `@model` directive will generate:
 - An Amazon DynamoDB table with PAY_PER_REQUEST billing mode enabled by default.