---
title: "An Assertion Retrieval Algebra for Object Queries over Knowledge Bases"
authors:
  - "Jeffrey Pound"
  - "David Toman"
  - "Grant E. Weddell"
  - "Jiewen Wu"
doi: "10.5591/978-1-57735-516-8/IJCAI11-180"
url: "https://ijcai.org/proceedings/2011/180"
pdf: "https://ijcai.org/proceedings/2011/0180.pdf"
venue: "Proceedings of the Twenty-Second International Joint Conference on Artificial Intelligence"
year: 2011
pages: "1051-1055"
track: ""
keywords:
---

# An Assertion Retrieval Algebra for Object Queries over Knowledge Bases

Jeffrey Pound, David Toman, Grant E. Weddell, Jiewen Wu

*Proceedings of the Twenty-Second International Joint Conference on Artificial Intelligence*, pages 1051-1055. DOI: [10.5591/978-1-57735-516-8/IJCAI11-180](https://doi.org/10.5591/978-1-57735-516-8/IJCAI11-180)

## Abstract

We consider a generalization of instance retrieval over knowledge bases that provides users with assertions in which descriptions of qualifying objects are given in addition to their identifiers. Notably, this involves a transfer of basic database paradigms involving caching and query rewriting in the context of an assertion retrieval algebra. We present an optimization framework for this algebra, with a focus on finding plans that avoid any need for general knowledge base reasoning at query execution time when sufficient cached results of earlier requests exist.