A Broad Class of First-Order Rewritable Tuple-Generating Dependencies
A Broad Class of First-Order Rewritable Tuple-Generating Dependencies
复制标题
广泛的一阶可重写元组生成依赖项
DOI：
10.1007/978-3-642-32925-8_8
复制
发表时间：
2012
期刊：
影响因子：
--
通讯作者：
R. Rosati
中科院分区：
文献类型：
--
作者：
Cristina Civili;R. Rosati
我们研究推理，特别是查询回答，在数据库与元组生成依赖关系（TGD）。我们的重点是TGD类的合取查询回答是一阶的，即，可以简化为对数据库的一阶查询的标准评估。在本文中，我们定义了类的弱递归TGD，并证明了这类包括和推广的所有以前已知的FOL-TGD类，在相当一般的假设下的形式的TGD。
We study reasoning, and in particular query answering, over databases with tuple-generating dependencies (TGDs). Our focus is on classes of TGDs for which conjunctive query answering is first-order rewritable, i.e., can be reduced to the standard evaluation of a first-order query over the database. In this paper, we define the class of weakly recursive TGDs, and prove that this class comprises and generalizes every previously known FOL-rewritable class of TGDs, under fairly general assumptions on the form of the TGDs.