A.6 Complex Data Rules

Table:	SOURCE
Description:	Source rows for a single part number cannot have two with the same priority.
Rule Logic:	(PART_NUMBER : PRIORITY) IS UNIQUE

Tables:	SOURCE, PURCHASE_ORDER
Description:	The quantity on a purchase order cannot be less than the minimum order quantity for the part.
Rule Logic:	PURCHASE_ORDER.QUANTITY <= SOURCE.MINIMUM_QUANTITY AND PURCHASE_ORDER.PART_NUMBER = SOURCE.PART_NUMBER

Tables:	PURCHASE_ORDER, INVENTORY
Description:	There should be no outstanding orders for parts that are marked Do not order.
Rule Logic:	(INVENTORY.PART_NUMBER = PURCHASE_ORDER.PART_NUMBER) AND (INVENTORY.DO_NOT_ORDER_FLAG = ‘D’) AND (PURCHASE_ORDER.STATUS = ‘P’ OR PUCHASE_ORDER.STATUS !=‘S’)
Note:	I wrote this rule as a negative: it selects offenders. It is much easier to express it this way than to express it as a positive state.