Simplified integrity checking for an expressive class of denial constraints

TL;DR

This paper introduces a method using program transformation to simplify complex denial constraints, including extended denials, making integrity checking more efficient and directly translatable into SQL for database systems.

Contribution

It proposes a novel approach to generate simplified integrity constraints from extended denials, enhancing automatic checking for complex data integrity conditions.

Findings

Applicable to standard database practices

Can be directly translated into SQL

Handles a broad class of denial constraints

Abstract

Data integrity is crucial for ensuring data correctness and quality, maintained through integrity constraints that must be continuously checked, especially in data-intensive systems like OLTP. While DBMSs handle common constraints well, complex constraints often require ad-hoc solutions. Research since the 1980s has focused on automatic and simplified integrity constraint checking, leveraging the assumption that databases are consistent before updates. This paper discusses using program transformation operators to generate simplified integrity constraints, focusing on complex constraints expressed in denial form. In particular, we target a class of integrity constraints, called extended denials, which are more general than tuple-generating dependencies and equality-generating dependencies. These techniques can be readily applied to standard database practices and can be directly translated into SQL.