Flexible transaction management in the InterBase project

Yungho Leu, Purdue University

Abstract

This thesis investigates various issues of transaction management in multidatabase systems. We identify the limitations in applying the traditional transaction model in multidatabase systems. Global transaction processing in multidatabase systems is subject to failure and may be long-lived. The traditional transaction model does not allow a transaction to fail partially and falls short of supporting long-lived transactions. We therefore propose an extended transaction model, called flex transaction, which captures more semantic information and thereby allows more flexibility in modeling and managing global transactions. Flex transactions provide the following features useful in a multidatabase system: (1) It allows the composition of flexible transactions which can tolerate failures of individual subtransactions by taking advantage of the fact that a given task of a transaction can frequently be achieved in more than one way; (2) It allows specification of dependencies on subtransactions; and (3) It supports controlled isolation which allows the co-existence of compensatable and non-compensatable subtransactions within a single global transaction. The flexible transaction feature allows a global transaction to have more than one way of execution. Execution of a global transaction fails only after exploring all of the possible ways of execution and none of them succeeds. This feature effectively minimizes the effects of failures on the execution of global transactions. Dependencies allow users to specify when and how to execute the subtransactions of a global transaction. The dependency information makes scheduling of the transaction execution more flexible.

Degree

Ph.D.

Advisors

Elmagarmid, Purdue University.

Subject Area

Computer science

COinS