On Query Containment Problem for Conjunctive Queries Under Bag-Set Semantics
Affiliation auteurs | Affiliation ok |
Titre | On Query Containment Problem for Conjunctive Queries Under Bag-Set Semantics |
Type de publication | Conference Paper |
Year of Publication | 2015 |
Auteurs | Felea V, Felea V |
Editor | Nguyen NT, Trawinski B, Kosala R |
Conference Name | Intelligent Information and Database Systems, Pt I |
Publisher | Bina Nusantara Univ; Wroclaw Univ Technol; Ton Duc Thang Univ; Quang Binh Univ; IEEE Indonesia Sect; IEEE SMC Tech Comm Computat Collect Intelligence |
Conference Location | GEWERBESTRASSE 11, CHAM, CH-6330, SWITZERLAND |
ISBN Number | 978-3-319-15702-3; 978-3-319-15701-6 |
Mots-clés | Bag-set semantics, Conjunctive queries, Query containment |
Résumé | The query containment is one of the fundamental problems in the context of query processing and optimization. Concerning the answers of queries for databases, three semantics were intensively analyzed. In the first one, called set, both databases and answers of queries for databases are considered sets. In the second one, called bag-set, databases are sets, but the answers are bags (multi-sets). In the third one, called bag, both databases and answers are bags. In this paper, we study the query containment problem for conjunctive queries (CQs) under bag-set semantics. It is not known whether this problem is decidable. We give a characterization of this problem. |
DOI | 10.1007/978-3-319-15702-3_16 |