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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.
-SELECT CID,CNAME FROM CUSTOMER HERE EXISTS
(SELECT CID FROM RENTALS
WHERE CUSTOMER.CID = RENTALS.CID
AND PICKUP = 'CARY')
The execution of this query lists the following CNAMEs:
Lithium Grease
A type of grease used for lubrication that is made from lithium soap, which is known for its high resistance to water and usefulness across a wide temperature range.
Service Life
The period during which a device, system, or component is expected to perform effectively and efficiently before requiring replacement or repair.
Snubber
A device that damps movement. Some fifth wheels are equipped with rubber block snubbers to damp trailer bump and pintle hook assemblies can be equipped with pneumatic (on-highway) or hydraulic (off-highway) snubbers.
Pintle Hook Assembly
A type of towing hitch system that uses a pintle hook and lunette ring, commonly used for heavy or military trailers.
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