Give three examples of applications in which certain transactions need not be totally isolated and, as a result, might return data which, although not the result of a serializable schedule, is adequate for the needs of the applications.
What will be an ideal response?
1. Deciding when to reorder merchandise in a store. A snapshot of the exact number
of each item in the current inventory might not be needed.
2. Printing out a mailing list of customers. The list printed out need not be a
snapshot of the customers at some particular instant, but might include some
people who are no longer customers or might not include some people who just
became customers.
3. When ordering tickets to a concert, the system might use two transactions: one
to display the available seats, and a second, executed later, to purchase tickets
and reserve seats. Each transaction is atomic, but the effect of executing both
transactions is not atomic — a seat might be reserved by a concurrent transaction
between the execution of the display and purchase transactions.
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Profile one of your recently written C/C++ programs. Write down all the commands that you used to accomplish this task.
What will be an ideal response?
Write a program that inputs a value for N and outputs how many chocolate bars we can eat and how many coupons we would have leftover. Use a loop that continues to redeem coupons as long as there are enough to get at least one chocolate bar.
Suppose we can buy a chocolate bar from the vending machine for $1 each. Inside every chocolate bar is a coupon. We can redeem 6 coupons for one chocolate bar from the machine. This means that once you have started buying chocolate bars from the machine, you always have some coupons. We would like to know how many chocolate bars can be eaten if we start with N dollars and always redeem coupons if we have enough for an additional chocolate bar. For example, with 6 dollars we could consume 7 chocolate bars after purchasing 6 bars giving us 6 coupons and then redeeming the 6 coupons for one bar. This would leave us with one extra coupon. For 11 dollars, we could have consumed 13 chocolate bars and still have one coupon left. For 12 dollars, we could have consumed 14 chocolate bars and have two coupons left. Students often attempt this problem by trying to find a simple formula instead of simulating the process in a loop. This also makes a good problem to re-do later after
Describe the guidelines for creating a secure password
What will be an ideal response?
The space between characters is called ____.
A. kerning B. leading C. tracking D. weighing