Determine DataSources Used in Reporting Services

USE ReportServer

/*Data Sources used in Reports*/
SELECT
  S.name AS 'Report Name'
	,C.Name AS 'DataSource'
FROM dbo.[Catalog] S (NOLOCK)
  INNER JOIN DataSource DS (NOLOCK) ON (s.ItemID = DS.ItemID)
  INNER JOIN dbo.[Catalog] C (NOLOCK) ON (DS.Link = C.ItemID)
WHERE
  S.Type = 2 --Type 2 is Report
ORDER BY 1

/*Data Sources used in Subscriptions*/
SELECT
  C.name
  ,S.Description
  ,C1.Name datasource
FROM dbo.Subscriptions S (NOLOCK)
	INNER JOIN DataSource DS (NOLOCK) ON (S.SubscriptionID = DS.SubscriptionID)
	INNER JOIN Catalog C1 (NOLOCK) ON (DS.Link = C1.ItemID)
	INNER JOIN dbo.Catalog C (NOLOCK) ON (C.ItemID = S.Report_OID)
WHERE
  C.Type = 2 --Type 2 is Report
ORDER BY 1