Improvement on Concurrency Control in a Distributed Database

ABSTRACT The study was conducted of the Improvement on concurrency control in a distributed database. The objectives of the study are to ensure consistent and correct transaction, efficient data collection and management and recoverability of data in a distributed database. The Mysql relational database was employed in collecting data for concurrency control protocols. The Unified Modeling Language (UML) was used in creating the use case, sequence diagram, class diagram and contract for the sequence diagram. Petri-nets a graphical tool for the analysis of sequence of operations in the distributed database was also used in this thesis. Finally MATLAB was applied to simulate the operation of concurrency control protocol in a distributed database. The result obtained from the improved concurrency control in a distributed database as developed in this thesis showed an improvement of 55% over the existing method of concurrency control in a distributed data base.

TABLE OF CONTENT

Title page - - - - - - - - - - i

Approval page- - - - - - - - - - ii

Declaration - - - - - - - - - - iii

Certification Page - - - - - - - - - iv

Dedication - - - - - - - - - - v

Acknowledgement - - - - - - - - - vi

Table of contents - - - - - - - - - vii

List of figures - - - - - - - - - - x

List of tables - - - - - - - - - - xii

Abstract - - - - - - - - - - xiii

CHAPTER ONE: INTRODUCTION 1

1.1Background to the study - - - - - - - - 1

1.2 statement of the problem - - - - - - - - 3

1.3 Objectives - - - - - - - - - 3

1.4 scope of study - - - - - - - - - 3

1.5 Significance of study - - - - - - - - 3

1.6 Plan/Organization of thesis - -- - - - - - 4

Chapter Two: LITERATURE REVIEW

2.1 History - - - - - - - - - - 5

2.2 Database - - - - - - - - - - 8

2.3 Database Analysis- - - - - - - - - 8

2.4 Database design and modeling - - - - - - - 11

2.5 Database management system - - - - - - - 13

2.6 Distributed database - - - - - - - - 14

2.7 Advantages of distributed database - - - - - - 16

2.8 Disadvantages of distributed database - - - - - - 18

2.9 Transaction - -- - - - - - - - 19

2.10 Concurrency control in a Distributed database - - - - - 22

2.11 concurrency control algorithm - - - - - - - 25

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2.11.1 Two-phase locking (2PL) - - - - - - - 25

2.11.2 Time stamp ordering - - - - - - - - 26

2.11.3 Wound-Wait (WW) - - - - - - - - 28

2.12 Models of concurrency - - -- - - - - - 28

2.12.1 Petri-nets - -- - - - - - - - 28

2.12.2 Process model - - - - - - - - - 33

2.12.3 Actor model - - - - - - - - - 36

2.13 Overview of the Project - - - - - - - - 37

2.13.1 Goals of the Project - - - - - - - - 39

2.13.2Software process improvement- - - -- - - - 40

2.13.3Functional requirements - - - - - - - 41

2.13.4 Data collection - - - - - - - - - 41

2.13.5 Data Duplication - - - - - - - - 41

2.13.6 Data Distribution - - - - - - - - 42

2.13.7 Distributed serializability - - - - - - - 42

2.13.8 Non-functional Requirements - -- - - - - - 44

2.13.9 Reliability - - - - - - - - - 44

2.13.10 Availability - - - - - - - - - 45

2.13.11 Recoverability - - - - - - - - 45

2.13.12 Maintainability - - - - - - - - 45

2.13.13 Software Requirement- - - - - - - - 45

2.13.14 The main architectures for parallel DBMS - - - - - 45

 2.14.1 Model of a Database management system - - - - - 47

2.5 Software design - - - - - - - - - 51

CHAPTER THREE: RESEARCH METHODOLOGY

3.1 Requirements Analysis and Specification - - - - - 53

3.1.1 Use Case diagram for concurrency control in a distributed database - - 53

3.1.2 Action diagram for concurrency control in a distributed database - - 54

3.1.3 Event Trace diagram for concurrency control in a distributed database- - 55

3.1.4 Sequence diagram for concurrency control in a distributed database - - 56

3.1.5 Class diagram for concurrency control in a distributed database - - 57

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3.1.6 Contract for the concurrency control in a distributed database - - - 58

3.2.0 Design process - - - - - - - - - 61

3.2.1 The Design Model- - - - - - - - - 61

3.2.2 Data design elements - - - - - - - - 62

3.2.3 Data diagram for concurrency control in a distributed database - - 62

3.3.1 An Improved Architecture for concurrency control in a distributed database - 65

3.4.1Petri net design approach - - - - - - - 67

3.4.2 Petri-nets Architectural design approach - - - - - 67

3.4.3 State Space design approach with a Petri-Net - - - - 68

CHAPTER FOUR: RESULTS AND DISCUSSION

4.1 Table for ONE-WAY concurrency control in a distributed database - - 85

4.1.1 Equation for the Simulation - - - - - - - 86

4.1.2 Simulation Process - - - - - - - - 86

4.2 Table for an improved TWO-WAY concurrency control in a distributed database - 88

4.2.1 Equation for the Simulation - - - - - - - 89

4.2.2 Simulation Process - -- - - - - - - 90

4.3. Table for an existing ONE-WAY concurrency control in a distributed database - 93

4.3.1 Equation for the Simulation - - - - - - - 93

4.3.2 Simulation Process - -- - - - - - - 94

4.4 Evaluation of the Results - - - - - - - - 96

4.4.1 Validating the analytical results with the Simulation Results. - -

4.4.2 Discussion on the improvement fn concurrency control in a distributed database - 96

CHAPTER FIVE: CONCLUSION AND RECOMMENDATION FOR FURTHER

WORK

5.1 Summary - - - - - - - - - - 99

5.2 Conclusion - - - - - - -- - - 99

5.3 Recommendation - - - - - - - - 99

5.4 Suggestions For Further Work - - - - - - - 99

References - - - - - - - - - - 100

Ahppendix - - - - - - - - - -