Table: 
PURCHASE_ORDER 

Description: 
Compute the number of orders for the same part in each month period and show all part numbers and the number of orders where the number is greater than three. 

Rule Logic: 
SELECT 
PART_NUMBER, MONTH(DATE_OF_ORDER),YEAR(DATE_OF_ORDER), COUNT (*) 
GROUP BY 
PART_NUMBER, 

WHERE 
COUNT(*) > 3 

Expectation: 
Expect none on the list. The inventory reordering algorithm should be ordering enough quantity not to have to reorder more than once a month. Multiple orders may be acceptable, but only under special circumstances. 
Table: 
PURCHASE_ORDER 

Description: 
Compute the total value of all purchase orders for a month by each category of inventory. Then compute the percentage of the total orders placed that each category provided. Compare this with historical distribution of orders. 

Rule Logic: 
SELECT 
INVENTORY.TYPE, 
FROM 
PURCHASE_ORDER. INVENTORY 

GROUP BY 
INVENTORY.TYPE 

WHERE 
INVENTORY.PART_NUMBER = 

Expectation: 
The percentage of the value of orders placed for each category should not vary from month to month by more than 10%. 