ลอง ประยุกต์ ดูนะครับ
$sql = 'SELECT sale_detail.Year,sale_detail.Month,
SUM(CASE WHEN sales_person_id.Sales_Zone= "International Sales" THEN sale_detail.Actual ELSE 0 END) As International,
SUM(CASE WHEN sales_person_id.Sales_Zone= "Zone 3" THEN sale_detail.Actual ELSE 0 END) As Zone3,
SUM(CASE WHEN sales_person_id.Sales_Zone= "Zone 4" THEN sale_detail.Actual ELSE 0 END) As Zone4,
SUM(CASE WHEN sales_person_id.Sales_Zone= "Zone 5" THEN sale_detail.Actual ELSE 0 END) As Zone5,
SUM(CASE WHEN sales_person_id.Sales_Zone= "สำนักงาน" THEN sale_detail.Actual ELSE 0 END) As office,
SUM(sale_detail.Actual) As GrandTotal
FROM sale_detail ,sales_person_id
WHERE sale_detail.Sales_Person_ID = sales_person_id.Sales_Person_ID
AND sale_detail.Year = "'.$year_s.'"
AND sale_detail.Month in (1,2,3,4,5,6,7,8,9,10,11,12)
GROUP BY sale_detail.Month';