Consider the following six relations for an order-processing database applicatio
ID: 3876325 • Letter: C
Question
Consider the following six relations for an order-processing database
application in a company:
CUSTOMER (Cust#, Cname, City)
ORDER (Order#, Odate, Cust#, OrdAmt)
ORDERITEM (Order#, Item#, Qty)
ITEM (Item#, Unitprice)
SHIPMENT (Order#, Warehouse#, Shipdate)
WAREHOUSE (Warehouse#, City)
Here, OrdAmt refers to total dollar amount of an order; Odate is the
date the order was placed; Shipdate is the date an order is shipped
from the warehouse. Assume that an order can be shipped from several
warehouses
Give an update operation to a database state that
violates an integrity constraint that is neither of the previous
kinds of constraints, stating any assumptions you make.
Explanation / Answer
Integrity constraint violations occur when an insert, update, or delete statement violates a primary key, foreign key, check, or unique constraint or a unique index.
When ORDERITEM (Order#, Item#, Qty) updates against the shipment by different where house the Order# will duplicate.
When SHIPMENT (Order#, Warehouse#, Shipdate) updates against the shipment by different where house the Order# will duplicate.