• Proceedings of the Korea Information Processing Society Conference
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• 2015.10a
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• pp.1128-1130
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• 2015

SQL 질의와 분산 처리를 위한 맵리듀스 함수를 통합 제공하면 쉽고 인터렉티브한 SQL 질의에서 맵리듀스 프로그래밍의 풍부한 표현력을 이용할 수 있다. 본 논문에서는 SQL 질의와 맵리듀스 함수를 통합하기 위해서 확장연산자를 이용하여 SQL 질의를 확장하는 방법을 제안한다.

• The KIPS Transactions:PartD
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• v.8D no.1
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• pp.1-9
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• 2001

The SQL CLl (Call Level Interface) is a database application programming interface (API) that fits the client-server environment, and its de facto standards such as ODBC and JDBC are widely employed in various applications. The current SQL CLl standards, however, do not specify enough features for efficient retrieval of large objects (LOBs) that constitute the multimedia data. In this paper, we propose the LOB caching through the SQL CLl and describe the extension of the SQL eLl to achieve such a goal. We implement our proposal by extending the SQL CLl library for BADA - II DBMS developed at ETRI, and evaluate the performance of LOB retrieval through the cache compared to that of LOB retrieval conducted solely with the functions specified in the current SQL CLl standards.

• ETRI Journal
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• v.27 no.4
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• pp.367-376
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• 2005

SQL/MDR is a metadata registry query language used to consistently exchange and share the data between distributed metadata registries. It is an extension of the international SQL and is familiar to most database builders and administrators. It provides many advantages such as simplicity of query language, ease of use, an independent description for distributed querying, low cost for adding new systems, simplicity of exchanging mechanism, and so on. The goal of this paper is to evaluate and show its merits quantitatively. To achieve this goal, we define simulation models to compare with an existing approach and then describe the evaluation results. In the quantitative evaluation results, the good points of SQL/MDR can be identified and known.

• Korean Journal of Remote Sensing
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• v.26 no.2
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• pp.133-142
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• 2010

As diverse web-based geos-spatial services are developed, the values of technologies and standards related to this trend are also emphasized. In this study, a prototype supporting mandatory components in OGC standard catalog service is designed and implemented, linked to PostgreSQL, open source DBMS. As the main features, XML metadata server was built with the helps of XML query functions in PostgreSQL. Given target applications with geo-spatial data sources and contents, this model can be applied, and it can be used for extension in other external web-based service systems or applications, because it supports international standard specifications.

• Proceedings of the Korean Information Science Society Conference
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• 2000.04b
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• pp.175-177
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• 2000

이기종 DB에 분산 저장되어 있는 데이터를 통합하여 사용자가 단일한 환경 내에서 각종 데이터를 접근, 관리할 수 있는 기술로써 멀티데이터베이TM 시스템(Multidatabase System:MDBS)이 연구되어 왔다. 그러나, 기존의 MDBS 는 사용하는 통합 모델에 따라 데이터 정의 언어나 데이터 처리 언어를 새로 정의하여 사용하였기 때문에, 지역 데이터베이스 시스템의 사용자는 새로운 데이터 모델과 데이터베이스 언어를 습득해야 하는 문제가 발생한다. 그러므로, 이를 해결하기 위해 현재 표준으로 진행되고 SQL3를 기반으로 한 MDBS의 개발이 요구된다. 본 논문에서는 SQL3를 확장한 멀티 데이터베이스 질의 언어(Multidatabase Query Language: MQL)를 제시하고 MQL을 이용한 3단계 스키마 통합 방안을 제안하고자 한다.

• Proceedings of the Korean Information Science Society Conference
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• 2000.04b
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• pp.84-86
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• 2000

XML은 다양한 정보이 표현이 가능하고 이들 정보의 구조적 표현이 가능하여 많은 연구 분야에서 사용되고 있다. 이러한, XML 문서의 효율적인 검색과 저장 관리를 위하여 데이터베이스 시스템을 이용한 연구가 활발히 진행되고 있으나 기존의 연구들은 XML 문서에 대한 질의 수행을 위해 SQL 과 독립된 질의 언어를 정의함으로써 데이터베이스와 통합된 질의를 제공하지 못한다. 본 논문에서는 XML 문서와 데이터베이스의 통합된 질의를 위하여 XML 문서의 엘리먼트를 자료형으로 정의하는 DDL 구문의 추가와 질의어에서 이들 자료형에 대한 연산을 지원하는 DML 의 확장을 한다. 제안한 질의어는 SQL을 이용하여 XML 문서에 대한 질의를 처리함으로써 XML 문서와 데이터베이스의 통합된 질의를 가능하게 한다.

• Journal of Korea Spatial Information System Society
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• v.9 no.2
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• pp.1-11
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• 2007

Recently, with the development of collecting methods of spatial data, the spatial data is produced, circulated, and used in various fields of industry and research. To manage the mass spatial data efficiently, the researches on extension of the existing commercial DBMS, such as ESRI's ArcSDE or Oracle's Oracle Spatial, is making progress actively. However, the usage of the extension of the commercial DBMS Incurs an additional expense and causes an interoperability problem due to differences in spatial data types and spatial operators. Therefore, in this paper, we developed an OpenGIS Spatial Interface for Oracle, which supports a standard interface by fellowing the "Simple Features Specification for SQL" proposed by OGC(Open Geospatial Consortium). Since the OpenGIS Spatial Interface provides all spatial data types and spatial operators proposed in "Simple Features Specification for SQL", users can manage mass spatial data of Oracle efficiently by using the standard interface without additional expense. In addition, we proved that the OpenGIS Spatial Interface is superior to the Oracle Spatial in the response time through the performance evaluation.

• Journal of the Korea Society of Computer and Information
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• v.9 no.4 s.32
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• pp.5-12
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• 2004

The data transformation between XML and Relation Database is made through the Principle of mapping bewtween them. There are two ways to access SQL Server, one is to assign SQL query to URL and the other is to use template file. MS-SQL server takes advantage of OpenXML function to transform the results of executing SQL query into XML documents. That is, OpenXML first makes node tree and then transforms row set data of XML documents into XML data of relation type. In order to insert XML data into database data. data is extracted from parsing XML documents using sp_xml_preparedocument procedure, and then the document structure is mapped into tree structure and stored in a table of database. Consequently, Data transformation between XML and Relation Database is made through mapping bewtween them. This article proposes the principle of mapping between XML and Relation Database and then shows the implementation of transformation between them so that it introduces the possibilty of bringing the extension and efficiency of data and various effects.

• Journal of Korea Multimedia Society
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• v.11 no.12
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• pp.1758-1764
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• 2008

In this paper, we propose query restructure method which realizes not only to present the result from database in Web page but also to adapt user's browsing environments. Recently, wireless PDA (Personal Digital Assistant) and portable phone and terminals equipped with Web browser become very popular. Various browsers would be required to create the HTML which adapt to the user's browsing environment. We propose an adaptive data presentation system which is an extension of SQL which creates HTML pages dynamically adapting to the size of screen. In our proposed method, the three basic rules for the layout conversion are provided and applying these rules, an efficient layout conversion technique optimized to user environment is proposed. Moreover, we propose a standard for converting layouts and a layout optimization for adaptive conversion of layouts.

• Journal of Korea Multimedia Society
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• v.2 no.2
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• pp.109-119
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• 1999

As the importance and utilization of multimedia data increase, we need to study representing and processing multimedia data within databases. To process multimedia data within databases, we need to precisely model multimedia data, to define data types and operations, and to make up query language supporting them. Therefore, in this paper, we modeled multimedia data using OMT so that we can support multimedia data within databases. We also propose an extended SQL, called MMSQl, which includes new types for supporting multimedia data types and efficiently make a query. Especially, MMSQL provides a mechanism to express temporal and spatial relationships which exist among objects in a multimedia data (internal) or among several multimedia data (external).