An Interval-Based Knowledge Model and Query Language for Temporal Information

1998 ◽

Vol 07 (03) ◽

pp. 319-339

Author(s):

X. SEAN WANG ◽

SUSHIL JAJODIA ◽

SONA MOHAVNI

Keyword(s):

Query Language ◽

Temporal Information ◽

Temporal Databases ◽

The Other ◽

Conversion Function ◽

Temporal Data ◽

Time Points ◽

User Query ◽

Simple Interface ◽

Time Point

In order to support uniform access to heterogeneous temporal information, we introduce the concept of a temporal mediator. A temporal mediator consists of three components: (i) a repository for windowing functions and conversion functions, (ii) a time granularity thesaurus and (iii) a query interpreter. There are two types of windowing functions: one associates each time point to a set of tuples, and the other associates each tuple to a set of time points. A conversion function transforms information in terms of one time granularity into that in terms of another time granularity. The time granularity thesaurus stores the knowledge about time granularities (e.g., names of time granularities and relationships among them). Users pose queries using the windowing functions and in terms of desired time granularities. (A query language, which can be used to form such queries, is given in the paper.) To answer such a user query, the query interpreter first employs the windowing functions together with the time granularity thesaurus to retrieve needed temporal data from the underlying databases and then uses the time granularity thesaurus to select suitable conversion functions which convert the responses to the desired time granularities. Thus, a temporal mediator provides a simple interface that supports uniform accesses to heterogeneous temporal databases.

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Modeling Temporal Information With JSON

Advances in Data Mining and Database Management - Emerging Technologies and Applications in Data Processing and Management ◽

10.4018/978-1-5225-8446-9.ch007 ◽

2019 ◽

pp. 134-153

Author(s):

Zhangbing Hu ◽

Li Yan

Keyword(s):

Data Exchange ◽

Query Language ◽

Rapid Development ◽

Life Time ◽

Transmission Efficiency ◽

Temporal Information ◽

Temporal Data ◽

Temporal Database ◽

Main Research ◽

Temporal Data Models

As a ubiquitous form of data in human natural life, time has been widely used in military, finance, medical treatment, environment and other fields. Therefore, temporal data models used to express the dynamic development process of data have been proposed constantly. Currently, the main research achievements focus on temporal database and temporal XML. With the rapid development and popularization of network technology, the requirement of efficiency and security is getting higher and higher. JSON, a new generation of data exchange language, has been widely used because of its lightweight, fast parsing and high transmission efficiency. However, modeling temporal information with JSON has not been studied enough. The chapter proposes a temporal data model based on JSON. What is more, the temporal query language and the JSON Schema is also mentioned.

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