Notwithstanding the traditional view that database instances must respect all integrity constraints imposed on them, it is relevant to develop theories about how to handle database instances that violate some integrity constraints, and more particularly, how to cope with query answering in the presence of inconsistency. Such a theory developed over the past twenty years is currently known as consistent query answering (CQA). The aim of this article is to summarize and discuss some core concepts and theoretical developments in CQA.

中文翻译：

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不一致数据库上的查询回答基础

尽管传统观点认为数据库实例必须尊重强加给它们的所有完整性约束，但开发有关如何处理违反某些完整性约束的数据库实例的理论，尤其是在存在不一致的情况下如何处理查询回答是相关的。在过去二十年中发展起来的这种理论目前被称为一致查询回答 (CQA)。本文的目的是总结和讨论 CQA 的一些核心概念和理论发展。