MySQL 5.7

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CREATE TABLE Uploads ( 
id int, 
Year int DEFAULT 2022, /* "DEFAULT 2022"  ADDED TO DEBLOCK THE EXAMPLE */
Week int, 
Division varchar(255), 
ProductGroupID varchar(255), 
Country varchar(255), 
Costumer varchar(255), 
POS varchar(255), 
SiteID varchar(255), 
Brand varchar(255), 
Product varchar(255), 
Inventory int NOT NULL, 
SoldUnits int NOT NULL DEFAULT 1, /* "DEFAULT 1"  ADDED TO DEBLOCK THE EXAMPLE */
Amount float NOT NULL );
insert into Uploads (Costumer, siteId, pos, week,
   Inventory, Amount) values
('customer A','00A1','posA1',	1,	67,	50),
('customer A','00A2','posA2',	1,	75,	45),
('customer A','00A3','posA3',	1,	98,	88),
('customer B','00B1','posB1',	1,	67,	50),
('customer C','00C1','posC1',	1,	67,	50),
('customer C','00C2','posC2',	1,	75,	45),
('customer B','00B1','posB1',	2,	67,	50),
('customer C','00C1','posC1',	2,	67,	50),
('customer C','00C2','posC2',	2,	75,	45),
('customer B','00B1','posB1',	3,	67,	50);
select
  c Customer,
  SiteId,
  pos,
  Week,
  sum(inventory) TotalInventory,
  sum(amount) TotalAmount
from 
( select
    costumer c,
    year y,
    max(week) w
  from Uploads
    where year= 2022
  group by costumer) lastWeek
join Uploads on c=costumer
and y=year and w=week
group by
  c,
  SiteId,
  pos,
  week


Customer
SiteId
pos
Week
TotalInventory
TotalAmount


customer A
00A1
posA1
1
67
50

customer A
00A2
posA2
1
75
45

customer A
00A3
posA3
1
98
88

customer B
00B1
posB1
3
67
50

customer C
00C1
posC1
2
67
50

customer C
00C2
posC2
2
75
45

Customer	SiteId	pos	Week	TotalInventory	TotalAmount
customer A	00A1	posA1	1	67	50
customer A	00A2	posA2	1	75	45
customer A	00A3	posA3	1	98	88
customer B	00B1	posB1	3	67	50
customer C	00C1	posC1	2	67	50
customer C	00C2	posC2	2	75	45