一句话：提出 FLIF，将 LIF 的一阶片段用于受限访问模式查询，等价于可执行一阶逻辑并翻译为查询计划。
信息流逻辑（LIF）是一种面向知识表示的声明式框架，可建模具有过程性的任务。本文关注数据库中的受限访问模式下的查询处理，并论证 LIF 适合刻画该问题。为此，作者在一阶设置下提出 FLIF，一种类似 XPath 的图导航语言，并证明它与 Nash 和 Ludäscher 定义的一阶逻辑可执行片段等价。FLIF 表达式中的变量可区分为输入和输出；当二者不相交时，称为 io-disjoint，可直接翻译为尊重访问限制的代数查询计划。最后，文章证明一般 FLIF 表达式总能转换为 io-disjoint 形式，从而保证可执行性。
The logic of information flows (LIF) has recently been proposed as a general framework in the field of knowledge representation. In this framework, tasks of procedural nature can still be modeled in a declarative, logic-based fashion. In this paper, we focus on the task of query processing under limited access patterns, a well-studied problem in the database literature. We show that LIF is well-suited for modeling this task. Toward this goal, we introduce a variant of LIF called "forward" LIF (FLIF), in a first-order setting. FLIF takes a novel graph-navigational approach; it is an XPath-like language that nevertheless turns out to be equivalent to the "executable" fragment of first-order logic defined by Nash and Lud\"ascher. One can also classify the variables in FLIF expressions as inputs and outputs. Expressions where inputs and outputs are disjoint, referred to as io-disjoint FLIF expressions, allow a particularly transparent translation into algebraic query plans that respect the access limitations. Finally, we show that general FLIF expressions can always be put into io-disjoint form.
@article{paperbot2758,
title = {Executable First-Order Queries in the Logic of Information Flows},
author = {Heba Aamer and Bart Bogaerts and Dimitri Surinx and Eugenia Ternovska and Jan Van den Bussche},
journal = {Logical Methods in Computer Science},
volume = {Volume 20, Issue 2},
year = {2024},
doi = {10.46298/lmcs-20(2:6)2024}
}