• Journal of the Korean Institute of Intelligent Systems
• /
• v.18 no.3
• /
• pp.306-310
• /
• 2008

XQuery is a new recommendation for XML query. As an efforts for extending XQuery capabilities XML insertion and deletion are being studied and its standardization are going on. Initially XML databases are developed simply for XML document management. Now their functions are extending to OLTP. In this paper we are adding updating functions to XQuery processing system that is developed only for XQuery retrievals. We suggest the structure of tables, numbering schemes for hierarchical structures, and the methods for SQL translations for XQuery updates.

• Journal of KIISE:Computing Practices and Letters
• /
• v.7 no.3
• /
• pp.202-210
• /
• 2001

Recently, XML is emerging as a web document standard and researches on storing and querying XML documents using existing RDBMS are actively in progress. In this paper, we propose a method that enables users to view and use XML documents like a relational table by extending concept of RDBMS's SQL view and. table function. In our approach, XML documents are existed independently of RDBMS and users can register relational schema of necessary part of XML document by using XML-View definition statement. Registered XML-View can be queried by SQL, and XML -table function is internally used so that XML - View can be accessed and used like a relational table. The proposed method enables users to access XML documents by providing the XML- View definition syntax and the table-function for existing RDBMS. Also, when schema modification for XML is needed, user can handle by modification of the XML- View definition.

• The Journal of Society for e-Business Studies
• /
• v.11 no.4
• /
• pp.33-48
• /
• 2006

Since the emergence of XML as the standard for data exchange on the Web, XML warehousing technology is required to efficiently support Web business applications such as e-Commerce. When the RDBMS is employed as the storage for XML warehouse, XML materialized views of the XML warehouse could be provided by leveraging the materialized views of the RDBMS Because XML documents are mapped into relational tuples, an XML query defining an XML materialized view needs to be transformed into SQL. If relational materialized views were defined with the transformed SQL statements, the XML materialized view could be obtained just by XML-tagging the tuples of the corresponding relational materialized views. The foremost advantage of such a scheme is that the RDBMS does take care of XML materialized view consistency except XML tagging whenever their source XML documents are updated. In this paper, we proposed such a scheme of providing XML materialized views, and implemented it using a commercial RDBMS equipped with materialized view facility in Java on Windows 2000 Professional environment. XML documents in TPC-W, Web e-Commerce Benchmark, were used in performance experiments. The experimental results showed that our proposed scheme for XML materialized views was very effective.

• Journal of the Korea Society of Computer and Information
• /
• v.6 no.1
• /
• pp.38-44
• /
• 2001

Nowadays, the study on XML as a standard method of exchange of information is active as Internet technology develops. This thesis designs and implements XML documents storage system using uniSQL/X in object-relational database. The system takes advantage of the merits of object-oriented databases, so that the structural information of XML documents can be effectively represented. The system uses split-storage method to allow frequent modifications of XML documents and suggests DTD-independent model so that it can store XML documents without DTD. And retrieval speed is improved by solving the issue of data duplication.

• Journal of the Korea Society of Computer and Information
• /
• v.15 no.11
• /
• pp.11-20
• /
• 2010

XML view is proposed to integrate between XML data and heterogeneous data over distributed environment and global XML view is used to search distributed heterogeneous data. At this time, standard query language for user is XQuery and the method for processing global XQuery queries over distributed environment is one of the new research topics. One of the basic and simple methods to process distributed SQL queries is that generates local queries for processing a global query and constructs the result of the global query from the results of the local queries. However, the syntax of XQuery differs from SQL because the XQuery contains some special expressions like FOR clauses for querying to semi-structured data, of course, FOR clauses are not used in SQL. Therefore, there are some problems to adopt the method for processing global SQL queries for generating local XQuery queries. This paper defines some problems when generates local XQuery queries for processing global XQuery queries and proposes a method for generating local XQuery queries considered these problems. Also we implement and evaluate a Global XQuery Processor which uses our method.

• Journal of KIISE:Computing Practices and Letters
• /
• v.10 no.5
• /
• pp.419-433
• /
• 2004

As XML becomes a standard for data representation, integration, and exchange on the Web, several XML query languages have been proposed. World Wide Web Consortium(W3C) has proposed XQuery as a standard for the XML query language. Like SQL, XQuery allows nested queries. Thus, normalization rules have been proposed to transform nested XQuery queries to semantically equivalent ones that could be executed more efficiently. However, previous normalization rules are applicable only to restricted forms of nested XQuery queries. Specifically, they can not handle FLWR expressions having nested expressions in the where clause. In this paper, we propose normalization rules for XQuery queries by extending those for SQL queries. Our proposed rules can handle FLWR expressions haying nested expressions in every clause. The major contributions of this paper are as follows. First, we classily nesting types of XQuery queries according to the existence of correlation and aggregation. We then propose normalization rules for each nesting type. Second, we propose detailed algorithms that apply the normalization rules to nested XQuery queries.

• Journal of Digital Contents Society
• /
• v.5 no.3
• /
• pp.180-186
• /
• 2004

XML has an essential funtion of dealing with standardized document to be used in all academic areas and industrial areas as well as e-commerce. The transformation of XML data into Relation Database table is also necessary for data search using SQL language. Mapping relation between XMLand Table in Relation Database is required for transformation of XML. This arti치e studies the mapping relation between XML and Relation Database using DTD which enables to check the unity automatically whenever document is read so that it studied mapping design for the transformation of XML data info Relation Database table.

• Proceedings of the Korean Information Science Society Conference
• /
• 2000.10a
• /
• pp.299-301
• /
• 2000

XML은 문서의 구조를 독립적으로 작성할 수 있어 문서의 체계적인 구조화가 가능하다. 이러한 이유로 최근, XML 문서를 구조화하여 데이터베이스에 저장, 관리하는 XML 문서 관리 시스템 연구가 활발하다. XML 문서 관리 시스템은 XML의 구조 정보를 효과적으로 표현하기 위해 여러 가지 기법을 사용하고 있다. 그러나, 기존의 방법들은 XML 문서 구성에 따라 저장 스키마가 유동적이거나 문서 정보 검색의 제약을 가지고 있을 뿐만 아니라, DTD의 문서 구조가 순환 관계와 같이 복잡한 형태를 지닐 때, 그 구조를 적절히 반영하지 못하거나, 구조를 반영하더라도 검색 시, 모든 요소를 순차적으로 탐색해야 하는 등의 문제점을 지니고 있다. 따라서 본 연구에서는 XML의 내용이나 구성에 영향받지 않는 저장 스키마를 설계하고 정보검색의 제약을 해결가능한 경로 정보를 제안한다. 또한 순환 관계를 갖는 DTD의 구조 정보를 비 순환 구조 부분과 순환 구조 부분으로 분리, 정의하고 질의처리 시, 입력되는 XML-QL을 SQL로 변환하기 위하여 XML-QL의 패턴을 분류하고 이에 따른 중간 단계의 SQL을 정의하여 질의어 변환기법을 제안한다.

• The KIPS Transactions:PartD
• /
• v.9D no.3
• /
• pp.381-388
• /
• 2002

XML documents, which are becoming new standard for expressing and exchanging data in the Internet, don't have defined schema. It is not adequate to directly apply XML documents to the existing SQL or OQL. Research on how to extract Schema for XML documents and query language is going on actively. For users' query, the results could be too tony or too less. It Is important to give the users adequate results. This paper suggests the way to extract many levelized schema according to the frequency of element occurrence in XML documents. The Schema can be reduced or extended to correspond to the users' query more flexibly.

• Journal of the Korea Computer Industry Society
• /
• v.3 no.5
• /
• pp.623-630
• /
• 2002

Method of designing and implementing the XML Gateway is proposed for supporting the data movement between the Legacy databases. XML technologies, Oracle XML Utility, and JDeveloper are used for this purpose. The data in Legacy database are extracted by XSQL pages, parsed, transformed by XSL, and finally saved by XMLHttprequest object of XSQL servlet. With the help of the implemented system, an assigned operator does not have to handle the database with the SQL＊Plus tools. In addition, the data movement is easily carried out by using the familiar Web interface offered by system.