Transaction Processing

Transaction Processing

Thomas Leich, Gunter Saake University of Magdeburg

Institute of Technical and Business Information Systems

Overview

1 Motivation

2 Transaction models

3 Transaction management

4 Advanced transaction models

5 Recovery and back-up

6 Distributed transactions

7 Replication

Required basic knowledge

Databases I:

Basic principles of database systems Tables, attributes, keys

Organization

Lecturer: Prof. Dr. Thomas Leich

Information (Timings, Room) & Slide copies can be found at

http://www.dbse.ovgu.de/Lehre/Lehrveranstaltungen/Transaction+Processing.html Lecture: Tuesday weekly Room: Online

Exercise:

I Exercise conductor: Gabriel Campero Durand I Exercise (voluntary):

F _{Zoom and video, Monday 07:00–09:00 (Begins: see Website)}

Examination:

I Writen or oral exam (If less than 35 participants) I Requirement: Registration for exercise

For feedback and questions:

I Mail to Gabriel Campero Durand

Underlying Textbook I

Saake, G.; Sattler, K.; Heuer, A.:

Datenbanken:

Implementierungstechniken.

Edition 3, mitp, 2011 644 Pages, 39,95 e Chapters 8, 9, 10

Underlying Textbook II

Rahm, E.; Saake, G.; Sattler, K.

Verteiltes und Paralleles Datenmanagement.

Von verteilen Datenbanken zu Big Data und Cloud

Edition 1, Springer, 2015 379 Pages

Chapters 11–15

Available as download!

Literature

For Database Implementation

Härder, T.; Rahm, E.: Datenbanksysteme — Konzepte und Techniken der Implementierung. Springer, 2001

Garcia-Molina, H.; Ullman, J.; Widom, J.: Database System Implementation. Addison-Wesley, 1999.

Silberschatz, A.; Korth, H. F.; Sudarshan, S.: Database System Concepts. Wiley & Sons, 2001.

For Transaction Processing:

Sippu, S.; Soisalon-Soininen, E.: Transaction Processing —

Management of the Logical Database and its Underlying Physical Structure. Springer, 2014

Weikum, G.; Vossen, G.: Transactional Information Systems — Theory, Algorithms, and the Practice of Concurrency Control and Recovery . Morgan Kaufmann, 2001

Gray, J.; Reuter, A.: Transaction Processing — Concepts and Techniques . Elsevier, 1992

Introduction

1. Introduction

1 Roles of Transactions

2 Transactions in the Architecture of a DBMS

Introduction

1. Introduction

1 Roles of Transactions

Introduction Transactions in the Architecture of a DBMS

Background

Introduction Transactions in the Architecture of a DBMS

Introduction Transactions in the Architecture of a DBMS

Tenth-floore test

Can I grab a random machine and throw it out the tenth-floor window without adversely impacting users for more than 10 minutes? If the answer to this was "yes", then we knew we were doing things right.

Introduction Transactions in the Architecture of a DBMS

Introduction Transactions in the Architecture of a DBMS

Example

Introduction Transactions in the Architecture of a DBMS

Introduction Transactions in the Architecture of a DBMS

Example

Introduction Transactions in the Architecture of a DBMS

Introduction Transactions in the Architecture of a DBMS

Example

Introduction Transactions in the Architecture of a DBMS

Introduction Transactions in the Architecture of a DBMS

Example

Introduction Transactions in the Architecture of a DBMS

Nine capabilities of a DBMS by Codd

1 Integration 2 Operations 3 Catalog 4 Views 5 Consistency Control 6 Data Protection 7 Transactions 8 Synchronization 9 Recovery

Introduction Transactions in the Architecture of a DBMS

Transaction properties

A transaction is a sequence of operations (actions), which transfers a database from a consistent state into another eventually changed

consistent state, applying the ACID properties.

Aspects:

I Semantic integrity: Correct (consistent) database state after the

end of transactions

I run-time integrity: Avoid errors caused by simultaneous access of

several users to the same data

Introduction Transactions in the Architecture of a DBMS

ACID Properties

Atomicity:

Transactions are either completed, or not performed at all.

Consistency:

If the database is in a consistent state before a transaction starts, the database is also consistent after the transaction has ended.

Isolation:

A user who is working on the database should not notice any other user working on it.

Durability:

The result of a transaction must be permanently stored within the database, after the transaction is completed.

Introduction Transactions in the Architecture of a DBMS

Architecture of DBMS

Sorting, Concurrency Control

Data Dictionary, Currency Pointer,

Page Replace Strategy

System Buffer Management with Translation, Acces Path Selection, Access Control, Integrity Control

Record Manager, Access Path Management, Lock Management, Log/Recovery

External Storage Management

Access System

Storage System

Buffer Management

Operating System Data System

Introduction Transactions in the Architecture of a DBMS

Storage hierarchy