There you go,
One customer, by part, and from this date to this date
SELECT
BKARHINV.BKAR_INV_CUSNME,
BKARHIVL.BKAR_INVL_PCODE,
BKARHIVL.BKAR_INVL_PDESC,
Sum(BKARHIVL.BKAR_INVL_PQTY) AS PQTY
FROM BKARHINV INNER JOIN BKARHIVL ON BKARHINV.BKAR_INV_NUM = BKARHIVL.BKAR_INVL_INVNM
WHERE BKARHINV.BKAR_INV_INVDTE > '2010-12-31' AND BKARHINV.BKAR_INV_INVDTE < '2012-01-01'
AND ASCII(LTRIM(RTRIM(BKARHIVL.BKAR_INVL_PCODE))) <> 0 AND BKARHINV.BKAR_INV_CUSCOD ='SCOENE0100'
GROUP BY BKARHINV.BKAR_INV_INVDTE, BKARHINV.BKAR_INV_CUSNME, BKARHIVL.BKAR_INVL_PCODE, BKARHIVL.BKAR_INVL_PDESC
ORDER BY BKARHINV.BKAR_INV_INVDTE DESC
Kelloggs