Lectures: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23

Overview

Read:

• Mohan, C., Bruce Lindsay, and R. Obermarck. "Transaction Management in the R* Distributed Database Management Systems." ACM Transactions On Database Systems 11, no. 4 (1986): 378-396.
• Also in Readings in Database Systems. San Fransisco, CA: Morgan Kaufmann, 1998. ISBN: 1558605231.

This paper discusses distributed transactions, addressing the problem of providing ACID-style semantics in a shared nothing environment.

As you read the papers, consider the following questions:

1. In the "R*" paper, how does the two phase commit (2PC) protocol work? What problem does it solve? What are the costs of using it?
2. What is the significance of the Presumed Abort/Presumed Commit variants of 2PC? How do they reduce the overhead of 2PC? When should you choose one over the other?