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Test Data Extraction and Comparison with Test Data Generation Utah State University DigitalCommons@USU All Graduate Theses and Dissertations Graduate Studies 8-2011 Test Data Extraction and Comparison with Test Data Generation Ali Raza Utah State University Follow this and additional works at: https://digitalcommons.usu.edu/etd Part of the Computer Sciences Commons Recommended Citation Raza, Ali, "Test Data Extraction and Comparison with Test Data Generation" (2011). All Graduate Theses and Dissertations. 982. https://digitalcommons.usu.edu/etd/982 This Thesis is brought to you for free and open access by the Graduate Studies at DigitalCommons@USU. It has been accepted for inclusion in All Graduate Theses and Dissertations by an authorized administrator of DigitalCommons@USU. For more information, please contact [email protected]. TEST DATA EXTRACTION AND COMPARISON WITH TEST DATA GENERATION by Ali Raza A thesis submitted in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE in Computer Science Approved: _______________________ _______________________ Stephen W. Clyde Vicki Allan Major Professor Committee Member _______________________ _______________________ Renée Bryce Byron R. Burnham Committee Member Dean of Graduate Studies UTAH STATE UNIVERSITY Logan, Utah 2011 ii Copyright © Ali Raza 2011 All Rights Reserved iii ABSTRACT Test Data Extraction and Comparison with Test Data Generation by Ali Raza, Master of Science Utah State University, 2011 Major Professor: Dr. Stephen W. Clyde Department: Computer Science Testing an integrated information system that relies on data from multiple sources can be a challenge, particularly when the data is confidential. This thesis describes a novel test data extraction approach, called semantic-based test data extraction for integrated systems (iSTDE ) that solves many of the problems associated with creating realistic test data for integrated information systems containing confidential data. iSTDE reads a consistent cross-section of data from the production databases, manipulates that data to obscure individual identities while still preserving overall semantic data characteristics that are critical to thorough system testing, and then moves that test data to an external test environment. This thesis also presents a theoretical study that compares test-data extraction with a competing technique, named test-data generation . Specifically, this thesis a) describes a comparison method that includes a comprehensive list of characteristics essential for testing the database applications organized into seven different areas, b) iv presents an analysis of the relative strengths and weaknesses of the different test-data creation techniques, and c) reports a number of specific conclusions that will help testers make appropriate choices. (122 pages) v ACKNOWLEDGMENTS To my father, who filled my life with light, love, and hope. May Allah rest his soul in eternal peace. To Dr. Clyde who guided my steps in this cumulative process. I would like to thank him for his invaluable assistance and support throughout my graduate career. To Dr. Vicki Allan and Dr. Renée Bryce for all their help and suggestions on this thesis. Ali Raza vi CONTENTS Page ABSTRACT .................................................................................................................... iii ACKNOWLEDGMENTS ...................................................................................................v LIST OF TABLES ............................................................................................................. ix LIST OF FIGURES .............................................................................................................x CHAPTER 1 INTRODUCTION ...................................................................................................1 2 BACKGROUND .....................................................................................................4 2.1 Subject Application: CHARM .........................................................................4 2.2 Problems Found in Testing of Integrated Systems ..........................................6 2.3 Personal Identifying Information and Anonymization ....................................7 2.3.1 Personally Identifiable Information (PII) ................................................7 2.3.2 Identification of PII throughTheir Impact Levels ....................................8 2.3.3 Ways of Hiding PII ..................................................................................9 2.4 Related Work .................................................................................................11 3 SEMANTIC-BASED TEST DATA EXTRACTION \ FOR INTEGRATED SYSTEMS (ISTDE) ...........................................................16 3.1 Overview ........................................................................................................16 3.2 Description of iSTDE Environment...............................................................17 3.3 Approach ........................................................................................................18 3.3.1 Specifying Extraction Parameters ..........................................................20 3.3.2 Creation of Temporary Databases .........................................................20 3.3.3 Extraction and Loading of Real Data to Temporary Databases ............24 3.3.4 PII Identification and Population ...........................................................26 3.3.5 Data Mangling .......................................................................................27 3.3.6 Transferring Mangled Data ....................................................................31 3.3.7 Destroying Mappings ..............................................................................32 3.4 Discussion of PII and Preserved Semantics in CHARM ...............................32 3.4.1 Identification of PII in CHARM ............................................................32 vii 3.4.2 Anonymizing PII in CHARM ................................................................33 3.4.3 List of Preserved Semantics in CHARM ...............................................33 3.5 Discussion of Extraction Set Size, Semantics Constraints and Mangling .....34 3.5.1 Size Constraints ................................................................................34 3.5.2 Exceptions ..........................................................................................34 3.6 Experience with iSTDE and Discussion ......................................................35 4 COMPARISON OF TEST DATA EXTRACTORSWITH TEST DATA GENERATORS .....................................................................................................37 4.1 Overview ........................................................................................................37 4.2 Two General Approaches to Test Data Creation ...........................................39 4.2.1 Data Generation .....................................................................................39 4.2.2 Data Extraction ......................................................................................44 4.3 Comparison Method.......................................................................................48 4.3.1 Overview ................................................................................................48 4.3.2 Comparison Context ..............................................................................52 5 COMPARISON RESULTS ...................................................................................54 5.1 Comparisons in the Context of Standalone Databases ........................54 5.2 Comparisons in the Context of Federated Databases ..........................69 5.3 Comparisons Related to Target Schemes ............................................71 5.4 Comparisons Related to Set-up, Use, and Performance ......................72 5.5 Comparisons in the Context of Database Refactoring .........................74 5.6 Comparisons in the Context of Testing Techniques ............................78 5.7 Comparisons Related to Social and Time Factors ...............................81 6 SUMMARY, FUTURE WORK, AND CONTRIBUTIONS ................................84 6.1 Summary ........................................................................................................84 6.2 Contributions..................................................................................................85 6.3 Future Extensions of iSTDE as a Tool ..........................................................87 6.4 Research Directions for Comparison ofTDGs and TDEs Approaches ..........88 REFERENCES ..................................................................................................................90 APPENDICES ....................................................................................................................... Appendix A ............................................................................................................94 viii Appendix B ............................................................................................................99 Appendix C ..........................................................................................................103 Appendix D ..........................................................................................................106 Appendix E ..........................................................................................................107 Appendix
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