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An index structure supporting rule activation in pervasive applications

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Yi Qin
Yi Qin
Yi Qin
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Xianping Tao
Xianping Tao
Xianping Tao
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Yu Huang
Yu Huang
Yu Huang
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Jian Lü
Jian Lü
Jian Lü
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Abstract and Figures

Rule mechanism has been widely used in many areas, such as databases, artificial intelligent and pervasive computing. In a rule mechanism, rule activation decides which rules are activated, when the rules are activated, and which tuples can be generated through the activation. Rule activation determines the efficiency of rule mechanism. In this article, we define the semantic constraints, constant constraint and variable constraint, of the rule according to the semantics of Datalog rules. Based on the constraints, we propose an index structure, named Yield index, to support the rule activation effectively. Yield index consists of the data index and semantic index, and records the complete information of a rule, including the matching relationship among the tuples of different relations in rule body. The index integrates tuple insertion and rule activation to directly determine whether the matching tuples of new inserted tuple exist. Due to this character, we perform effective rule activation only, avoiding ineffective rule activation that cannot generate new tuples, so that the efficiency of rule activation is improved. The article describes the structure of Yield index, the construction and maintenance algorithms, and the rule activation algorithm based on Yield index. The experimental results show that Yield index has better performance and improves activation efficiency of one order of magnitude, comparing with other index structures. In addition, we also discuss the possible extensions of Yield index in other applications.
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https://doi.org/10.1007/s11280-017-0517-2
An index structure supporting rule activation
in pervasive applications
Yi Qin1·Xianping Tao1·Yu Hua n g 1·Jian L ¨
u1
Received: 22 July 2017 / Revised: 16 October 2017 / Accepted: 22 November 2017
© Springer Science+Business Media, LLC, part of Springer Nature 2018
Abstract Rule mechanism has been widely used in many areas, such as databases, artifi-
cial intelligent and pervasive computing. In a rule mechanism, rule activation decides which
rules are activated, when the rules are activated, and which tuples can be generated through
the activation. Rule activation determines the efficiency of rule mechanism. In this arti-
cle, we define the semantic constraints, constant constraint and variable constraint, of the
rule according to the semantics of Datalog rules. Based on the constraints, we propose an
index structure, named Yield index, to support the rule activation effectively. Yield index
consists of the data index and semantic index, and records the complete information of
a rule, including the matching relationship among the tuples of different relations in rule
body. The index integrates tuple insertion and rule activation to directly determine whether
the matching tuples of new inserted tuple exist. Due to this character, we perform effective
rule activation only, avoiding ineffective rule activation that cannot generate new tuples,
so that the efficiency of rule activation is improved. The article describes the structure of
Yield index, the construction and maintenance algorithms, and the rule activation algorithm
based on Yield index. The experimental results show that Yield index has better perfor-
mance and improves activation efficiency of one order of magnitude, comparing with other
index structures. In addition, we also discuss the possible extensions of Yield index in other
applications.
Yi Qin
borakirchies@163.com
Xianping Tao
txp@nju.edu.cn
Yu Hua n g
yuhuang@nju.edu.cn
Jian L¨
u
lj@nju.edu.cn
1State Key Laboratory for Novel Software Technology and Department of Computer Science
and Technology, Nanjing University, Xianling Road No.163, Nanjing, China
World Wide Web (2019) 22:1–37
/
Published online: 19 February 2018
Content courtesy of Springer Nature, terms of use apply. Rights reserved.
... TREAT is a tuple-centric network that records all po-965 tential useful tuples in a network. The recent published work, Yield Index [47], is similar to discrimination networks. It connects the matching tuples through its semantic index that is organized on top of its data index to speed up the update. ...
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