How to check SQL server DB role membership

This is the TSQL to check the membership of a db role in MS SQL Server

SELECT DP1.name AS DatabaseRoleName,   
   isnull (DP2.name, 'No members') AS DatabaseUserName   
 FROM sys.database_role_members AS DRM  
 RIGHT OUTER JOIN sys.database_principals AS DP1  
   ON DRM.role_principal_id = DP1.principal_id  
 LEFT OUTER JOIN sys.database_principals AS DP2  
   ON DRM.member_principal_id = DP2.principal_id  
WHERE DP1.type = 'R'
ORDER BY DP1.name;