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Figuer:
CUSTOMER In table CUSTOMER, CID is the primary key (Customer ID) .
RENTALS In the table RENTALS, RTN provides the rental number (the primary key) , CID is the customer's unique id, PICKUP is the city where the car was picked up, and Return is the city where the car was returned.
RENTCOST RENTCOST shows the base cost of renting a given MAKE for one day.
CITYADJ If the return city of table RENTALS is the one listed in table CITYADJ, the cost of the rental is multiplied by FACTOR and by DAYS shown in table RENTLENGTH below.
RENTLENGTH RENTLENGTH shows the number of days for the rental number (RTN) shown in table RENTALS. In a database used in reality, this table would be merged with the RENTALS table.
-(ACCESS) DELETE RENTALS.* FROM RENTALS INNER JOIN CUSTOMER
ON CUSTOMER.CID = RENTALS.CID
AND CNAME IN ('BLACK','SIMON') )
The execution of this query deletes the following number of rows from the table RENTALS:
Value Added
The enhancement a company gives its product or service before offering the product to customers, essentially the difference between the cost of inputs and the value or price of outputs.
Raw Materials
The basic materials from which products are made, typically extracted natural resources or agricultural products.
Circular Flow Model
An economic model depicting how money moves through the economy between producers and consumers.
Resource Market
A market where resources or inputs needed for production, such as labor, capital, and raw materials, are bought and sold.
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