Abstract
Symbolic execution is a technique enabling the automatic generation of test inputs that exercise a set of execution paths within a code unit to be tested. If the paths cover a sufficient part of the code under test, the test data offer a representative view of the actual behaviour of this code. This notably enables detecting errors and correcting faults. Relational databases are ubiquitous in software, but symbolic execution of code units that manipulate them remains a non-trivial problem, particularly because of the complex structure of such databases and the complex behaviour of SQL statements. Finding errors in such code units is yet critical, as it can avoid corrupting important data. In this work, we define a symbolic execution translating database manipulation code directly into constraints and integrate it with a more traditional symbolic execution of normal program code. The database tables are represented by relational symbols and the SQL statements by relational constraints over these symbols. An algorithm based on these principles is presented for the symbolic execution of simple Java methods that implement transactional use cases by reading and writing in a relational database, the latter subject to data integrity constraints. The algorithm is integrated in a test generation tool and experimented over sample code. The target language for the constraints produced by the tool is the SMT-Lib standard and the used solver is Microsoft Z3. The results show that the proposed approach enables generating meaningful test data, including valid database content, in reasonable time. In particular, the Z3 solver is shown to be more scalable than the Alloy solver, used in our previous work, for solving relational constraints.
Original language | English |
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Pages (from-to) | 44-72 |
Number of pages | 29 |
Journal | Science of Computer Programming |
Volume | 105 |
Early online date | 10 Apr 2015 |
DOIs | |
Publication status | Published - 1 Jul 2015 |
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Keywords
- Software Testing
- Symbolic Execution
- Constraints
- Satisfiability Modulo Theories (SMT)
- Alloy
- Quantifiers
- First-Order Logic
- Relational Algebra
- Structured Query Language (SQL)
- Database
- Database Applications
Cite this
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Relational symbolic execution of SQL code for unit testing of database programs. / Marcozzi, Michaël; Vanhoof, Wim; Hainaut, Jean Luc.
In: Science of Computer Programming, Vol. 105, 01.07.2015, p. 44-72.Research output: Contribution to journal › Article
TY - JOUR
T1 - Relational symbolic execution of SQL code for unit testing of database programs
AU - Marcozzi, Michaël
AU - Vanhoof, Wim
AU - Hainaut, Jean Luc
PY - 2015/7/1
Y1 - 2015/7/1
N2 - Symbolic execution is a technique enabling the automatic generation of test inputs that exercise a set of execution paths within a code unit to be tested. If the paths cover a sufficient part of the code under test, the test data offer a representative view of the actual behaviour of this code. This notably enables detecting errors and correcting faults. Relational databases are ubiquitous in software, but symbolic execution of code units that manipulate them remains a non-trivial problem, particularly because of the complex structure of such databases and the complex behaviour of SQL statements. Finding errors in such code units is yet critical, as it can avoid corrupting important data. In this work, we define a symbolic execution translating database manipulation code directly into constraints and integrate it with a more traditional symbolic execution of normal program code. The database tables are represented by relational symbols and the SQL statements by relational constraints over these symbols. An algorithm based on these principles is presented for the symbolic execution of simple Java methods that implement transactional use cases by reading and writing in a relational database, the latter subject to data integrity constraints. The algorithm is integrated in a test generation tool and experimented over sample code. The target language for the constraints produced by the tool is the SMT-Lib standard and the used solver is Microsoft Z3. The results show that the proposed approach enables generating meaningful test data, including valid database content, in reasonable time. In particular, the Z3 solver is shown to be more scalable than the Alloy solver, used in our previous work, for solving relational constraints.
AB - Symbolic execution is a technique enabling the automatic generation of test inputs that exercise a set of execution paths within a code unit to be tested. If the paths cover a sufficient part of the code under test, the test data offer a representative view of the actual behaviour of this code. This notably enables detecting errors and correcting faults. Relational databases are ubiquitous in software, but symbolic execution of code units that manipulate them remains a non-trivial problem, particularly because of the complex structure of such databases and the complex behaviour of SQL statements. Finding errors in such code units is yet critical, as it can avoid corrupting important data. In this work, we define a symbolic execution translating database manipulation code directly into constraints and integrate it with a more traditional symbolic execution of normal program code. The database tables are represented by relational symbols and the SQL statements by relational constraints over these symbols. An algorithm based on these principles is presented for the symbolic execution of simple Java methods that implement transactional use cases by reading and writing in a relational database, the latter subject to data integrity constraints. The algorithm is integrated in a test generation tool and experimented over sample code. The target language for the constraints produced by the tool is the SMT-Lib standard and the used solver is Microsoft Z3. The results show that the proposed approach enables generating meaningful test data, including valid database content, in reasonable time. In particular, the Z3 solver is shown to be more scalable than the Alloy solver, used in our previous work, for solving relational constraints.
KW - Software Testing
KW - Symbolic Execution
KW - Constraints
KW - Satisfiability Modulo Theories (SMT)
KW - Alloy
KW - Quantifiers
KW - First-Order Logic
KW - Relational Algebra
KW - Structured Query Language (SQL)
KW - Database
KW - Database Applications
UR - http://www.scopus.com/inward/record.url?scp=84929704309&partnerID=8YFLogxK
U2 - 10.1016/j.scico.2015.03.005
DO - 10.1016/j.scico.2015.03.005
M3 - Article
AN - SCOPUS:84929704309
VL - 105
SP - 44
EP - 72
JO - Science of Computer Programming
JF - Science of Computer Programming
SN - 0167-6423
ER -