Merhaba;
Aşağıdaki şekilde dener misiniz?
İyi çalışmalar.

SELECT WeekdayName(Weekday([TARİH]),False,1) AS GUN, Count([GUN]) AS GUNADET, sum(BLOK_YÜK.TAKOZ_TOPLAM) AS ToplaTAKOZ_TOPLAM

FROM BLOK_YÜK

GROUP BY WeekdayName(Weekday([TARİH]),False,1);