SELECT ISNULL(MYDATE,'None') AS MYDATE,
ISNULL(CAST(rnm AS NVARCHAR(50)),'None') AS Rnm,
DATENAME(dw, MYDATE) as nameOfDay,
FROM tab1
INNER JOIN rnm ON (tab1.rte = rnm.rte)
WHERE DATEDIFF(S, '1970-01-01', MYDATE) >= :startDate
AND DATEDIFF(S, '1970-01-01', MYDATE) <= :endDate
GROUP BY MYDATE, CAST(rnm AS NVARCHAR(50)) WITH ROLLUP