C e n t r u m v o o r W i s k u n d e e n I n f o r m a t i c aSymphony: View-Driven Software Architecture Reconstruction ABSTRACT Authentic descriptions of a software architecture are required as a reliable foundation for any but trivial changes to a system. Far too often, architecture descriptions of existing systems are out of sync with the implementation. If they are, they must be reconstructed. There are many existing techniques for reconstructing individual architecture views, but no information about how to select views for reconstruction, or about process aspects of architecture reconstruction in general. In this paper we describe view-driven process for reconstructing software architecture that fills this gap. To describe Symphony, we present and compare different case studies, thus serving a secondary goal of sharing real-life reconstruction experience. The Symphony process incorporates the state of the practice, where reconstruction is problemdriven and uses a rich set of architecture views. Symphony provides a common framework for reporting reconstruction experiences and for comparing reconstruction approaches. Finally, it is a vehicle for exposing and demarcating research problems in software architecture reconstruction. ACM Computing Classification

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.

Abstract

Abstract

SUMMARYIn the field of database applications a considerable part of the business logic is implemented using a semi-declarative language: the Structured Query Language (SQL). Because of the different semantics of SQL compared to other procedural languages, the conventional coverage criteria for testing are not directly applicable. This paper presents a criterion specifically tailored for SQL queries (SQLFpc). It is based on Masking Modified Condition Decision Coverage (MCDC) or Full Predicate Coverage and takes into account a wide range of the syntax and semantics of SQL, including selection, joining, grouping, aggregations, subqueries, case expressions and null values. The criterion assesses the coverage of the test data in relation to the query that is executed and it is expressed as a set of rules that are automatically generated and efficiently evaluated against a test database. The use of the criterion is illustrated in a case study which includes complex queries.