MODA: automated test generation for database applications via mock objects

Software testing has been commonly used in assuring the quality of database applications. It is often prohibitively expensive to manually write quality tests for complex database applications. Automated test generation techniques, such as Dynamic Symbolic Execution (DSE), have been proposed to reduce human efforts in testing database applications. However, such techniques have two major limitations: (1) they assume that the database that the application under test interacts with is accessible, which may not always be true; and (2) they usually cannot create necessary database states as a part of the generated tests. To address the preceding limitations, we propose an approach that applies DSE to generate tests for a database application. Instead of using the actual database that the application interacts with, our approach produces and uses a mock database in test generation. A mock database mimics the behavior of an actual database by performing identical database operations on itself. We conducted two empirical evaluations on both a medical device and an open source software system to demonstrate that our approach can generate, without producing false warnings, tests with higher code coverage than conventional DSE-based techniques.