Mutating database queries

Abstract

Abstract.A set of mutation operators for SQL queries that retrieve information from a database is developed and tested against a set of queries drawn from the NIST SQL Conformance Test Suite. The mutation operators cover a wide spectrum of SQL features, including the handling of null values. Additional experiments are performed to explore whether the cost of executing mutants can be reduced using selective mutation or the test suite size can be reduced by using an appropriate ordering of the mutants. The SQL mutation approach can be helpful in assessing the adequacy of database test cases and their development, and as a tool for systematically injecting faults in order to compare different database testing techniques.

Automatic test generation for mutation testing on database applications

“…Then, at each query-issuing point, we get the symbolic query and invoke the tool SQLMutation [13] to generate its mutants. SQLMutation automatically generates SQL-query mutants (providing each mutant's form, type, and generation rule) based on a set of mutation operators [14] for SQL queries. As mentioned in Section II, the mutation operators are organized into four categories of which the SC operators mainly focus on the main clauses (e.g., SELECT clause) and the other operators (OR, NL, and IR) focus on the conditions in the WHERE clause.…”

“…Mutation testing was also applied in testing database applications. Tuya et al [13], [14] proposed a set of mutation operators for SQL queries and integrated these operators into a tool called SQLMutation that generates SQL-query mutants automatically. Shah et al [10] proposed an approach that focuses in particular on a class of join/outer-join mutations, comparison operator mutations, and aggregation operation mutations.…”

“…Mutation testing would produce a set of mutants (each being the software under test systematically seeded with a small fault) and then measure how high percentage of these mutants are killed (i.e., detected) by the tests under assessment. Other than traditional mutation testing where mutants exist in normal program code, Tuya et al [13], [14] proposed a set of mutation operators for SQL queries and developed a tool called SQLMutation that implements these mutation operators to generate SQL-query mutants. To assess the adequacy of tests for Java database applications, Zhou and Frankl [18] developed a tool called JDAMA based on the mutation operators for SQL queries [14].…”

“…Tuya et al [14] proposed a set of mutation operators and developed SQLMutation [13] that implements this set of mutation operators to generate SQL-query mutants. These mutation operators are organized into four categories: SC -SQL clause mutation operators: mutation of the most distinctive features of SQL (e.g., clauses, aggregate functions).…”

“…Thus, applying weak mutation testing by seeding faults [14] to the queries can reflect the adequacy of the associated test database states.…”