Select
  @GroupId= CASE @WorkTypeId
        WHEN 1 THEN (SELECT COALESCE(@GroupId+',' ,'') + CAST(GroupId as VARCHAR(2)) as groupId1 FROM UserGroupRoleMapping
                WHERE UserId= @UserId and IsActive=1 AND GroupId != 4)
        WHEN 3 THEN (SELECT COALESCE(@GroupId+',' ,'') + CAST(GroupId as VARCHAR(2)) as groupId1 FROM UserGroupRoleMapping
                WHERE UserId= @UserId and IsActive=1 AND GroupId = 4)
        ELSE (SELECT COALESCE(@GroupId+',' ,'') + CAST(GroupId as VARCHAR(2)) as groupId1 FROM UserGroupRoleMapping
                WHERE UserId= @UserId and IsActive=1)