a. Example for using normal transaction undo mechanism : Consider a bank account S with balance $200. Let two transactions individually deposit $20 in the account. Thus, the final balance should be $240. Now, when the transactions are executed in sequence T 1 , T 2 the log records would be as follows: < T 1 , S, 200, 220 > < T 2 , S, 220, 240 > Now, transaction T 1 needs to be undone...

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Answer 1

Expert Solution & Answer

Chapter 19, Problem 11PE

Explanation of Solution

a.

Example for using normal transaction undo mechanism:

Consider a bank account S with balance $200.

Let two transactions individually deposit $20 in the account. Thus, the final balance should be $240.

Now, when the transactions are executed in sequence T₁, T₂ the log records would be as follows:
< T₁, S, 200, 220 >

< T₂, S, 220, 240 >

Now, transaction T₁ needs to be undone...

Explanation of Solution

b.

Implementing point-in-time recovery using database dumps:

To modify the recovery algorithm from section 19.4 to implement point in time recovery using database dumps;

Identify the latest archival dump (say D) before the start of the erroneous transaction (say Te) that is < Te, start>.

Restore the database using this dump D.

Now, perform a redo of all log records starting from the dump till the transaction committed that is < Te, commit >.

Let S be the set of those transactions which were active at the commit time of Te.

Rollback all transactions in the set S including Te...

Explanation of Solution

c.

Re-executing non-erroneous transactions logically:

To understand the reason the later non-erroneous transactions cannot be re-executed logically using log records, consider again the example from part (a);

Let both the transactions be undone and the balance be reverted back to $200.

Now, if T₂ needs to be redone while using the log record < T₂, ...

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After playing our giving implementation, your task is to implement Dinning Philosophers with semaphore in C, by including and Your implementation will require creating five philosophers, each identified by a number 0.4. Each philosopher will run as a separate thread. Create threads using Pthreads as discussed in the Lecture slides on Chapter 4 and Practice Lab on Threads. Your solution needs to accomplish the following: Implement in C (15 points) 1. dp1.c - You are to provide your solution to this assignment as a single C program named 'dp1.c using semaphore. Explain in you code (as comments) that the dead lock will happen or not. If there is a possible deadlock, you can simply solve the deadlock by pick the fork in order like the first solution in our slides. Solve Deadlock by Footman (15 points) 1. Here is a new solution to overcome the deadlock. The Dining Philosophers decide to hire a footman whose task to allow only four philosophers to sit on the table. When entering and…

8.4 Self-Bias Configuration 20. Determine Zi. Zo. and A,, for the network of Fig. 8.73 if gf, = 3000 μS and gos = 50 μs. 21. Determine Z, Zo, and A, for the network of Fig. 8.73 if the 20-uF capacitor is removed and the parameters of the network are the same as in Problem 20. Compare results with those of Problem 20. +12 V 3.3 ΚΩ HE C₂ Vo Z Zo C₁ 10 ΜΩ Z₁ 1.1 ΚΩ Cs 20 µF FIG. 8.73 Problems 20, 21, 22, and 59.

21. Determine Zi, Zo, and A, for the network of Fig. 8.73 if the 20-μF capacitor is removed and the parameters of the network are the same as in Problem 20. Compare results with those of Problem 20. +12 V 3.3 ΚΩ +6 C₂ C₁ Z₁ 10 ΜΩ 1.1 ΚΩ Cs 20 μF FIG. 8.73 Zo

Answer 2

Expert Solution & Answer

Chapter 19, Problem 11PE

Explanation of Solution

a.

Example for using normal transaction undo mechanism:

Consider a bank account S with balance $200.

Let two transactions individually deposit $20 in the account. Thus, the final balance should be $240.

Now, when the transactions are executed in sequence T₁, T₂ the log records would be as follows:
< T₁, S, 200, 220 >

< T₂, S, 220, 240 >

Now, transaction T₁ needs to be undone...

Explanation of Solution

b.

Implementing point-in-time recovery using database dumps:

To modify the recovery algorithm from section 19.4 to implement point in time recovery using database dumps;

Identify the latest archival dump (say D) before the start of the erroneous transaction (say Te) that is < Te, start>.

Restore the database using this dump D.

Now, perform a redo of all log records starting from the dump till the transaction committed that is < Te, commit >.

Let S be the set of those transactions which were active at the commit time of Te.

Rollback all transactions in the set S including Te...

Explanation of Solution

c.

Re-executing non-erroneous transactions logically:

To understand the reason the later non-erroneous transactions cannot be re-executed logically using log records, consider again the example from part (a);

Let both the transactions be undone and the balance be reverted back to $200.

Now, if T₂ needs to be redone while using the log record < T₂, ...

Expert Solution & Answer

Want to see the full answer?

Check out a sample textbook solution

See solution

Answer 3

Expert Solution & Answer

Chapter 19, Problem 11PE

Explanation of Solution

a.

Example for using normal transaction undo mechanism:

Consider a bank account S with balance $200.

Let two transactions individually deposit $20 in the account. Thus, the final balance should be $240.

Now, when the transactions are executed in sequence T₁, T₂ the log records would be as follows:
< T₁, S, 200, 220 >

< T₂, S, 220, 240 >

Now, transaction T₁ needs to be undone...

Explanation of Solution

b.

Implementing point-in-time recovery using database dumps:

To modify the recovery algorithm from section 19.4 to implement point in time recovery using database dumps;

Identify the latest archival dump (say D) before the start of the erroneous transaction (say Te) that is < Te, start>.

Restore the database using this dump D.

Now, perform a redo of all log records starting from the dump till the transaction committed that is < Te, commit >.

Let S be the set of those transactions which were active at the commit time of Te.

Rollback all transactions in the set S including Te...

Explanation of Solution

c.

Re-executing non-erroneous transactions logically:

To understand the reason the later non-erroneous transactions cannot be re-executed logically using log records, consider again the example from part (a);

Let both the transactions be undone and the balance be reverted back to $200.

Now, if T₂ needs to be redone while using the log record < T₂, ...

Expert Solution & Answer

Want to see the full answer?

Check out a sample textbook solution

See solution

Answer 4

Expert Solution & Answer

Chapter 19, Problem 11PE

Explanation of Solution

a.

Example for using normal transaction undo mechanism:

Consider a bank account S with balance $200.

Let two transactions individually deposit $20 in the account. Thus, the final balance should be $240.

Now, when the transactions are executed in sequence T₁, T₂ the log records would be as follows:
< T₁, S, 200, 220 >

< T₂, S, 220, 240 >

Now, transaction T₁ needs to be undone...

Explanation of Solution

b.

Implementing point-in-time recovery using database dumps:

To modify the recovery algorithm from section 19.4 to implement point in time recovery using database dumps;

Identify the latest archival dump (say D) before the start of the erroneous transaction (say Te) that is < Te, start>.

Restore the database using this dump D.

Now, perform a redo of all log records starting from the dump till the transaction committed that is < Te, commit >.

Let S be the set of those transactions which were active at the commit time of Te.

Rollback all transactions in the set S including Te...

Explanation of Solution

c.

Re-executing non-erroneous transactions logically:

To understand the reason the later non-erroneous transactions cannot be re-executed logically using log records, consider again the example from part (a);

Let both the transactions be undone and the balance be reverted back to $200.

Now, if T₂ needs to be redone while using the log record < T₂, ...

Expert Solution & Answer

Want to see the full answer?

Check out a sample textbook solution

See solution

Answer 5

Expert Solution & Answer

Answer 6

Expert Solution & Answer

Answer 7

Chapter 19, Problem 11PE

Explanation of Solution

a.

Example for using normal transaction undo mechanism:

Consider a bank account S with balance $200.

Let two transactions individually deposit $20 in the account. Thus, the final balance should be $240.

Now, when the transactions are executed in sequence T₁, T₂ the log records would be as follows:
< T₁, S, 200, 220 >

< T₂, S, 220, 240 >

Now, transaction T₁ needs to be undone...

Explanation of Solution

b.

Implementing point-in-time recovery using database dumps:

To modify the recovery algorithm from section 19.4 to implement point in time recovery using database dumps;

Identify the latest archival dump (say D) before the start of the erroneous transaction (say Te) that is < Te, start>.

Restore the database using this dump D.

Now, perform a redo of all log records starting from the dump till the transaction committed that is < Te, commit >.

Let S be the set of those transactions which were active at the commit time of Te.

Rollback all transactions in the set S including Te...

Explanation of Solution

c.

Re-executing non-erroneous transactions logically:

To understand the reason the later non-erroneous transactions cannot be re-executed logically using log records, consider again the example from part (a);

Let both the transactions be undone and the balance be reverted back to $200.

Now, if T₂ needs to be redone while using the log record < T₂, ...

Answer 8

Chapter 19, Problem 11PE

Explanation of Solution

a.

Example for using normal transaction undo mechanism:

Consider a bank account S with balance $200.

Let two transactions individually deposit $20 in the account. Thus, the final balance should be $240.

Now, when the transactions are executed in sequence T₁, T₂ the log records would be as follows:
< T₁, S, 200, 220 >

< T₂, S, 220, 240 >

Now, transaction T₁ needs to be undone...

Answer 9

Chapter 19, Problem 11PE

Explanation of Solution

a.

Example for using normal transaction undo mechanism:

Consider a bank account S with balance $200.

Let two transactions individually deposit $20 in the account. Thus, the final balance should be $240.

Now, when the transactions are executed in sequence T₁, T₂ the log records would be as follows:
< T₁, S, 200, 220 >

< T₂, S, 220, 240 >

Now, transaction T₁ needs to be undone...

Answer 10

Explanation of Solution

b.

Implementing point-in-time recovery using database dumps:

To modify the recovery algorithm from section 19.4 to implement point in time recovery using database dumps;

Identify the latest archival dump (say D) before the start of the erroneous transaction (say Te) that is < Te, start>.

Restore the database using this dump D.

Now, perform a redo of all log records starting from the dump till the transaction committed that is < Te, commit >.

Let S be the set of those transactions which were active at the commit time of Te.

Rollback all transactions in the set S including Te...

Answer 11

Explanation of Solution

b.

Implementing point-in-time recovery using database dumps:

To modify the recovery algorithm from section 19.4 to implement point in time recovery using database dumps;

Identify the latest archival dump (say D) before the start of the erroneous transaction (say Te) that is < Te, start>.

Restore the database using this dump D.

Now, perform a redo of all log records starting from the dump till the transaction committed that is < Te, commit >.

Let S be the set of those transactions which were active at the commit time of Te.

Rollback all transactions in the set S including Te...

Answer 12

Explanation of Solution

c.

Re-executing non-erroneous transactions logically:

To understand the reason the later non-erroneous transactions cannot be re-executed logically using log records, consider again the example from part (a);

Let both the transactions be undone and the balance be reverted back to $200.

Now, if T₂ needs to be redone while using the log record < T₂, ...

Answer 13

Explanation of Solution

c.

Re-executing non-erroneous transactions logically:

To understand the reason the later non-erroneous transactions cannot be re-executed logically using log records, consider again the example from part (a);

Let both the transactions be undone and the balance be reverted back to $200.

Now, if T₂ needs to be redone while using the log record < T₂, ...

Answer 14

Expert Solution & Answer

Answer 15

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Answer 16

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Answer 17

Ch. 19 - Prob. 1PE Ch. 19 - Prob. 2PE Ch. 19 - Prob. 3PE Ch. 19 - Prob. 4PE Ch. 19 - Prob. 5PE Ch. 19 - Prob. 6PE Ch. 19 - Prob. 7PE Ch. 19 - Prob. 8PE Ch. 19 - Prob. 9PE Ch. 19 - Prob. 10PE

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