Exercise 7.5.2: Write the following as triggers. In each case,disallow or
undo the modification if it does not satisfy the stated constraint.The database
schema is from the “PC” example of Exercise 2.4.1:
Product(maker, model, type)
PC(model, speed, ram, hd, price)
Laptop(model, speed, ram, hd, screen, price)
Printer(model, color, type, price) ! c) When making any modification to the Laptop relation, checkthat the
average price of laptops for each manufacturer is at least$1500.
! d) When updating the RAM or hard disk of any PC, check that theupdated
PC has at least 100 times as much hard disk as RAM.
! e) When inserting a new PC, laptop, or printer, make sure thatthe model
number did not previously appear in any of PC, Laptop, orPrinter. . . .
A Foreign Institutional Investor (FII) invested in Indian capital market on December 01,2000. When the Mumbai stock exchange sensex was quoting at 3800. The rupee-dollar ...Apr 20 2021
Tech Company is a medium-sized consumer electronics retailer. The company reported $155,000,000 in revenues for 2007 and $110,050,000 in Costs of Goods Sold (COGS). In th...Aug 01 2020
Carbon tetrachloride can be produced by which reaction?Jul 26 2021
Man enterprises is working on a bid to build two apartment buildings a year for the next 5 years for a local college. this project requires the purchase $1,000,000 of equ...Apr 29 2021
Suppose you want to convert U.S. dollars to Indian rupees. If you have $120,000 and the exchange rate is $0.0159 per rupee, how many rupees (in millions) will you receive...Aug 05 2021
Demand for a product is forecasted for the six periods is 263, 256,301,312, 304, and 294 respectively, if a CHASE DEMAND strategy is adopted, and the regular production c...May 02 2021
10. (5pt) The base of S is the region enclosed by the curve y=sinx and the x-axis. Cross-sections perpendicular to the x-axis are equilateral triangles. Find the volume o...Apr 13 2021
When profit-maximizing firms in competitive markets are earning profits,A. market demand must exceed market supply at the market-equilibium price.B. market supply must ex...Jun 01 2018
It was a dark and stormy night when suddenly you saw a flash of lightning. Six and a half seconds later you heard the thunder. Given that the speed of sound in air is abo...Apr 01 2020
The income statement in which the total of all expenses is deducted from the total of all revenues is termed:(A) report form.(B) account form.(C) single-step form.(D) mul...May 21 2018