Question: Suppose two-phase locking is used, but exclusive locks are released early, that is, locking is not done in a strict two-phase manner. Give an example

Suppose two-phase locking is used, but exclusive locks are released early, that is, locking is not done in a strict two-phase manner. Give an example to show why transaction rollback can result in a wrong final state, when using the log based recovery algorithm.

Step by Step Solution

★★★★★

3.34 Rating (157 Votes )

There are 3 Steps involved in it

1 Expert Approved Answer

Step: 1 Unlock

Consider two transactions T1 and T2 both of which read and wri... View full answer

Question Has Been Solved by an Expert!

Get step-by-step solutions from verified subject matter experts

Step: 2 Unlock

Step: 3 Unlock

Students Have Also Explored These Related Database System Concepts Questions!

Give an example to show that the converse of Corollary 11.5 need not be true.

Give an example to show that (a b) = a b

Give an example to show that (a + b) a + b

Database Administration CHAPTER OBJECTIVES I Understand the need for and importance of database I ttno'illI the meaning of ACID transaction administralin - Learn the tour 1992 ANSI standard isolation...

Portray in words what transforms you would have to make to your execution to some degree (a) to accomplish this and remark on the benefits and detriments of this thought.You are approached to compose...

A creative engineer suggests structuring the TLB so that not all the bits of the presented address need match to result in a hit. Suggest how this might be achieved, and what might be the costs and...

Suppose that R(A, B, C) is a relational schema with functional dependencies F = {A, B C, C B}. (i) Is this schema in 3NF? Explain. [2 marks] (ii) Is this schema in BCNF? Explain. [2 marks] (b)...

Prolog You are approached to compose a Prolog program to work with twofold trees. Your code shouldn't depend on any library predicates and you ought to expect that the mediator is running without...

Ice at 0C is placed in a Styrofoam cup containing 361 g of a soft drink at 23C. The specific heat of the drink is about the same as that of water. Some ice remains after the ice and soft drink reach...

Samar Company has the following balance on Dec 31,2019; Credit Sale Cash sale Accounts Receivable Provision for doubtful debt BD 950,000 BD 700,000 BD 150,000 BD 180 Required: Record the bad debts...

Which of the following statements is true about advanced filtering?

What is the correlation between VERBAL and QUANTITATIVE?

Write down the binary representation of the decimal number 63.25 assuming it was stored using the single precision IBM format (base 16, instead of base 2, with 7 bits of exponent).

Write down the binary bit pattern to represent -1.5625 10 -1 assuming a format similar to that employed by the DEC PDP-8 (the left most 12 bits are the exponent stored as a twos complement number,...

IEEE 754-2008 contains a half precision that is only 16 bits wide. The left most bit is still the sign bit, the exponent is 5 bits wide and has a bias of 15, and the mantissa is 10 bits long. A...

PR 22-5A Budgeted Income statement an3 balance sheet As a preliminary to requesting buciget estima:es of sales, costs, and expenses for the fiscal OBJ. 4,5 year beginning January 1, 2017, the...

Problem 12-2 (Algo) Trading securities; bond investment; effective Interest [LO12-1, 12-3] Fuzzy Monkey Technologies, Inc., purchased as a short-term investment $60 million of 6% bonds, dated January...

3-3B - Adjusting Entries, the Adjusted Trial Balance Worksheet, Financial Statements, Closing Entries (and the kitchen sink.) a.) A count of supplies reveals $50 were on hand on September 30 . b.)...