In the script, write this
Testing:
LOAD
Sector,
[Material No],
Plant,
Year,
Month,
[Order Qty],
[Sch Qty],
[STO Qty],
[Opening Stock],
if(sum([Order Qty])+sum([STO Qty])>sum([Sch Qty])+sum([Opening Stock]),'Alert','Ok') as Alert
FROM
C:\Users\akki\Desktop\MBEWH.xlsx
(ooxml, embedded labels, table is Sheet1);
Then in pie chart take Alert as dimension, and add the expression as Count(Alert).
This will give you the count of OKs and Alerts in the pie chart
