Computer Science: An Overview (13th Edition) (What's New in Computer Science)
13th Edition
ISBN: 9780134875460
Author: Glenn Brookshear, Dennis Brylow
Publisher: PEARSON
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Expert Solution & Answer
Chapter 9, Problem 43CRP
Explanation of Solution
Incorrect information in the schedule of transactions
- The sequence of transaction is:
- Transaction
- Transaction
- Transaction
- Transaction
- The step (ii) adds the amount of
- When step (iii) retrieves the value of B, it is not true value but the value of B after addition of
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A very large number of Customer objects must be added to the database.
Each time a new object is to be added, the following statement is executed
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if (number>=capacity)
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i.
with the new size as specified above, number+1?
ii.
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iii.
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Each Semuarasa restaurant branch has a mainstay menu that is very popular with customers, so information on the availability of the number of servings is needed to be able to serve orders. Here are two transactions that are ordering a food menu at the same time.
T1: Start the transaction at time t1, read 10 servings of food stock at t2. Because ordering one portion, the stock is reduced by 1 at t3. On t6, update the stock count, and commit to t7.
T2: Transaction T2 starts a transaction on t2, reads the number of stocks in t3 as many as 10. At t4 orders 3 portions. On t5 it updates the stock to 7 and then on t6 commits it.
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Database (Transaction Management)
Each branch of the Jaja restaurant has a mainstay menu that is very popular with customers, so information on the availability of the number of servings is needed to be able to serve orders. Here are two transactions that are ordering a food menu at the same time.
T1: Start the transaction at time t1, read 10 servings of food stock at t2. Because ordering one portion, the stock is reduced by 1 at t3. On t6, update the stock count, and commit to t7.
T2: Transaction T2 starts a transaction on t2, reads the number of stocks in t3 as many as 10. At t4 orders 3 portions. On t5 it updates the stock to 7 and then on t6 commits it.
As a result of the T1 and T2 transactions above, there was an error in the amount of food stocks. Make a solution with 2PL. What kinds of problems happened? Give a reason why choosing this type of problem! How much food is still available?
Chapter 9 Solutions
Computer Science: An Overview (13th Edition) (What's New in Computer Science)
Ch. 9.1 - Identify two departments in a manufacturing plant...Ch. 9.1 - Prob. 2QECh. 9.1 - Summarize the roles of the application software...Ch. 9.2 - Prob. 1QECh. 9.2 - Prob. 2QECh. 9.2 - Prob. 4QECh. 9.2 - Prob. 5QECh. 9.2 - Prob. 6QECh. 9.3 - Prob. 1QECh. 9.3 - What is a persistent object?
Ch. 9.3 - Identify some classes as well as some of their...Ch. 9.3 - Prob. 4QECh. 9.4 - Prob. 1QECh. 9.4 - Prob. 2QECh. 9.4 - Prob. 3QECh. 9.4 - Prob. 4QECh. 9.4 - Prob. 5QECh. 9.4 - Prob. 6QECh. 9.5 - Prob. 1QECh. 9.5 - Prob. 2QECh. 9.5 - Prob. 3QECh. 9.5 - Prob. 4QECh. 9.5 - Prob. 5QECh. 9.5 - Prob. 6QECh. 9.5 - Prob. 7QECh. 9.6 - Prob. 1QECh. 9.6 - Give an additional example of a pattern that might...Ch. 9.6 - Prob. 3QECh. 9.6 - How does data mining differ from traditional...Ch. 9.7 - Prob. 1QECh. 9.7 - Prob. 2QECh. 9.7 - Prob. 3QECh. 9.7 - Prob. 4QECh. 9 - Prob. 1CRPCh. 9 - Prob. 2CRPCh. 9 - Prob. 3CRPCh. 9 - Prob. 4CRPCh. 9 - Prob. 5CRPCh. 9 - Prob. 6CRPCh. 9 - Prob. 7CRPCh. 9 - Prob. 8CRPCh. 9 - Prob. 9CRPCh. 9 - Prob. 10CRPCh. 9 - Prob. 11CRPCh. 9 - Prob. 12CRPCh. 9 - Using the commands SELECT, PROJECT, and JOIN,...Ch. 9 - Answer Problem 13 using SQL. PROBLEM 13 13. Using...Ch. 9 - Prob. 15CRPCh. 9 - Prob. 16CRPCh. 9 - Prob. 17CRPCh. 9 - Prob. 18CRPCh. 9 - Prob. 19CRPCh. 9 - Empl Id Name Address SSN Job Id Job Title Skill...Ch. 9 - Empl Id Name Address SSN Job Id Job Title Skill...Ch. 9 - Prob. 22CRPCh. 9 - Prob. 23CRPCh. 9 - Prob. 24CRPCh. 9 - Prob. 25CRPCh. 9 - Write a sequence of instructions (using the...Ch. 9 - Prob. 27CRPCh. 9 - Prob. 28CRPCh. 9 - Prob. 29CRPCh. 9 - Prob. 30CRPCh. 9 - Prob. 31CRPCh. 9 - Prob. 32CRPCh. 9 - Prob. 33CRPCh. 9 - Prob. 34CRPCh. 9 - Prob. 35CRPCh. 9 - Prob. 36CRPCh. 9 - Prob. 37CRPCh. 9 - Prob. 38CRPCh. 9 - Prob. 39CRPCh. 9 - Prob. 40CRPCh. 9 - Prob. 41CRPCh. 9 - Prob. 42CRPCh. 9 - Prob. 43CRPCh. 9 - Prob. 44CRPCh. 9 - Prob. 45CRPCh. 9 - Prob. 46CRPCh. 9 - Prob. 47CRPCh. 9 - Prob. 48CRPCh. 9 - Prob. 49CRPCh. 9 - Prob. 50CRPCh. 9 - Prob. 51CRPCh. 9 - Prob. 52CRPCh. 9 - Prob. 53CRPCh. 9 - Prob. 54CRPCh. 9 - Prob. 55CRPCh. 9 - Prob. 56CRPCh. 9 - Prob. 57CRPCh. 9 - Prob. 58CRPCh. 9 - Prob. 59CRPCh. 9 - Prob. 60CRPCh. 9 - Prob. 61CRPCh. 9 - Prob. 62CRPCh. 9 - Prob. 1SICh. 9 - Prob. 2SICh. 9 - Prob. 3SICh. 9 - Prob. 4SICh. 9 - Prob. 5SICh. 9 - Prob. 6SICh. 9 - Prob. 7SICh. 9 - Prob. 8SICh. 9 - Prob. 9SICh. 9 - Prob. 10SI
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