Clarified roles prereq for child objects in ADF.

Author: douglaslMS

includes/data-factory-quickstart-prerequisites.md

@@ -18,6 +18,8 @@ If you don't have an Azure subscription, create a [free account](https://azure.m
 ### Azure roles
 To create Data Factory instances, the user account that you use to sign in to Azure must be a member of the *contributor* or *owner* role, or an *administrator* of the Azure subscription. In the Azure portal, select your username in the upper-right corner, and select **Permissions** to view the permissions that you have in the subscription. If you have access to multiple subscriptions, select the appropriate subscription. For sample instructions on adding a user to a role, see the [Add roles](../articles/billing/billing-add-change-azure-subscription-administrator.md) article.
 
+To create and manage child resources (including datasets, linked services, pipelines, triggers, and integration runtimes) for Data Factory through the Author & Monitor UI in the Azure portal, you must belong to the **Data Factory Contributor** role. To create and manage child resources with Powershell or the SDK, the **contributor** role is sufficient.
+
 ### Azure storage account
 You use a general-purpose Azure storage account (specifically Blob storage) as both *source* and *destination* data stores in this quickstart. If you don't have a general-purpose Azure storage account, see [Create a storage account](../articles/storage/common/storage-quickstart-create-account.md) to create one.