Technical gazette, Vol. 27 No. 3, 2020.
Original scientific paper
https://doi.org/10.17559/TV-20191123110408
Query with Assumptions for Probabilistic Relational Databases
Caicai Zhang
; School of Information Science and Technology, Jiujiang University, No. 551, Qianjin East Road, Jiujiang, Jiangxi 332005, China
Zhuolin Mei
; School of Information Science and Technology, Jiujiang University, No. 551, Qianjin East Road, Jiujiang, Jiangxi 332005, China
Bin Wu
; School of Information Science and Technology, Jiujiang University, No. 551, Qianjin East Road, Jiujiang, Jiangxi 332005, China
Zhiqiang Zhao
; School of Information Science and Technology, Jiujiang University, No. 551, Qianjin East Road, Jiujiang, Jiangxi 332005, China
Jing Yu
; School of Information Science and Technology, Jiujiang University, No. 551, Qianjin East Road, Jiujiang, Jiangxi 332005, China
Qingqing Wang
; School of Information Science and Technology, Jiujiang University, No. 551, Qianjin East Road, Jiujiang, Jiangxi 332005, China
Abstract
Users may have prior knowledge about a probabilistic database. They prefer to query over a probabilistic database on their prior knowledge which cannot be written as component clauses of conventional SQL queries. A naive approach is to query over a new database version, which is generated by transforming the original probabilistic database to satisfy users' prior knowledge; however, it is impractical to generate a different probabilistic database version for each prior knowledge. In this paper, we propose the concept of the query with assumptions which allow users to describe their prior knowledge with a newly introduced ASSUMPTION clause of SQL. We also propose an approach to obtain the result of a query based on assumption clauses. The experimental studies show our approach has better performance compared to the naive approach.
Keywords
probabilistic database; prior knowledge; query with assumptions
Hrčak ID:
239103
URI
Publication date:
14.6.2020.
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