We consider the recommendations of the World Wide Web Consortium (W3C) about RDF framework and its associated query language SPARQL. We propose a new formal framework based on category theory which provides clear and concise formal definitions of the main basic features of RDF and SPARQL. We define RDF graphs as well as SPARQL basic graph patterns as objects of some nested categories. This allows one to clarify, in particular, the role of blank nodes. Furthermore, we consider basic SPARQL CONSTRUCT and SELECT queries and formalize their operational semantics following a novel algebraic graph transformation approach called POIM.

中文翻译：

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RDF和SPARQL的代数图变换方法

我们考虑了万维网联合会（W3C）关于RDF框架及其相关查询语言SPARQL的建议。我们提出了一个基于类别理论的新形式框架，该框架为RDF和SPARQL的主要基本特征提供了简洁明了的形式定义。我们将RDF图以及SPARQL基本图模式定义为某些嵌套类别的对象。这使人们尤其可以澄清空白节点的作用。此外，我们考虑了基本的SPARQL CONSTRUCT和SELECT查询，并根据一种称为POIM的新颖代数图转换方法来形式化它们的操作语义。