Relational symbolic execution of SQL code for unit testing of database programs

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.

A Surwey of Automated Testing Tools

“…We conclude that N-Unit is the best tool among all three. The next phase of this paper would deal with the selection of open source testing tools for java and python, object oriented test cases for object identification using reflection, entity framework model utilization, ranking those tools based on their associated attributes like usefulness, recording of test cases, efficiency, reuseability of test cases, sync test cases and their results with some online repository to make them use in future projects and many other things shows huge gap in this field which needs to be filled slowly, gradully and with accuracy of authentic results which can be best fit and thought out for further investigation in this field [10] [11].…”

Update Algorithm of Secure Computer Database Based on Deep Belief Network

“…These three units cooperate with each other and are responsible for different work contents. Two-out-of-three security computer consists of three systems, each of which has an ATP unit, and the three ATP units among the three systems are connected by point-to-point Ethernet [25][26][27][28]. There is an ATO unit in the first and second series of three series, but there is no ATO unit in the third series.…”