G. E. Blake, M. P. Consens, P. Kilpelainen, P.-A. Larson, T. Snider, and F. W. Tompa. Text/relational database management systems: Harmonizing sql and sgml. In Proceedings of the International Conference on Applications of Databases, pages 267--280, June 1994.  Home/Search   Document Not in Database   Summary   Related Articles   Check

....distinct factor that a#ects performance. 4. RELATED WORK A substantial amount of work has been done on integrating information retrieval, especially text searching, with database systems. Examples of integrating text search with relational, object relational, or object oriented databases include [4, 39, 11]. Commercial examples include the DB2 Text Extender [18] and Oracle InterMedia Text [27] An example of integrating text search with semi structured databases is Lore [23] in which a simplified version of an IR style text index is used to locate strings containing specific text words or groups ....

....or groups of text words [22] None of this previous work explores the performance implications of a special purpose vs. native implementation of this functionality in an RDBMS. The advent of SGML [15] has triggered much research on integrating content and structure in text retrieval, in cluding [3, 38, 4, 30]. Work on containment queries can be found in [7, 8, 10] Our work on containment queries di#ers from the previous work in that, since we target XML rather than SGML data retrieval, and XML elements are strictly nested, we are not concerned with overlapped extents, nor with reduction functions on ....

G. E. Blake, M. P. Consens, P. Kilpelainen, P.-A. Larson, T. Snider, and F. W. Tompa. Text/relational database management systems: Harmonizing sql and sgml. In Proceedings of the International Conference on Applications of Databases, pages 267--280, June 1994.

.... [28, 35] The distinction between data and structure seems to disappear, at least for the end users: strict typing becomes counterproductive; complex and large schemata are created; queries and updates frequently address both, data and schema [3] As it has been pointed out by many researches [42, 37, 14, 9, 10], the use of Database Management Systems (DBMS) for the administration of digital libraries offers many advantages: concurrent access and on line updates, version management, declarative query languages, users authentication, recovery and protection of the stored information. However, conventional ....

....that arises is then, how SGML documents can be represented on a DBMS model in an optimal way. It has been illustrated by previous research work on this field, that the hierarchical structure of SGML documents can be more naturally represented using object oriented models than relational ones [9]. Many recent studies focus on the representation of SGML documents on object oriented DBMSs [14, 31, 10] As practised so far, there exist two conflicting mapping strategies: a so called generic mapping (i.e. minimally structured) and a DTD specific one (i.e. maximally structured) The ....

G. Blake, M. Consens, P. Kilpelainen, and P. Larson. Text/Relational Database Management Systems: Harmonizing SQL and SGML. In ADBA'94, pages 267--280, 1994.

....structured documents. The fact that parsed documents closely resemble database structures has been used to propose extensions of query languages capable of manipulating text. However, all of these proposals are based on a form of grammatical pre processing of textual information (see, for example, [23, 28, 40, 4, 12, 16, 18]) In essence, when the textual database is created, each document is pre processed to generate suitable data structures, such as the parse tree associated with the document string or indexes used to access important regions in the text. Then, query processing is based on these structures. When ....

G. E. Blake, M. P. Consens, P. Kilpelainen, P. Larson, T. Snider, and F. W. Tompa. Text/relational database management systems: Harmonizing SQL and SGML. In First Intern. Conf. on Applications of Databases, (ADB'94), Vadstena, Sweden. LNCS 819, pages 267--280. Springer-Verlag, June 1994.

....the advantages of a declarative, grammar based approach, with the flexibility of procedural programming in handling heterogeneities and exceptions. 1.1. Grammars and Exceptions Languages and tools for wrapper generation were first studied in the context of textual databases (see, for example, [10, 9, 19]) and then with specific reference to semi structured data [23, 48] and the Web [28, 14] All of these approaches use variants of grammars to describe patterns in documents. Unfortunately, a little experience with the World Wide Web shows that items in 2 Crescenzi and Mecca HTML pages can ....

G. E. Blake, M. P. Consens, P. Kilpelainen, P. Larson, T. Snider, and F. W. Tompa. Text/relational database management systems: Harmonizing SQL and SGML. In First Intern. Conf. on Applications of Databases, (ADB'94), Vadstena, Sweden. LNCS 819, pp. 267--280. Springer-Verlag (1994).

....describing structured documents. The fact that parsed documents closely resemble database structures has been used to propose extensions of query languages capable of manipulating text. However, all of these proposals are based on a form of pre processing of textual information (see, for example, [22, 26, 38, 4, 12, 15, 17]) In essence, when the textual database is created, each document is preprocessed to generate suitable data structures, such as the parse tree associated with the document string or indexes used to access important regions in the text. Then, query processing is based on these structures. When ....

G. E. Blake, M. P. Consens, P. Kilpelainen, P. Larson, T. Snider, and F. W. Tompa. Text/relational database management systems: Harmonizing SQL and SGML. In First Intern. Conf. on Applications of Databases, (ADB'94), Vadstena, Sweden. LNCS 819, pages 267-- 280. Springer-Verlag, June 1994.

....pieces using certain conventions or at least conversion mechanisms that are agreed upon between the many different representation and interchange formats available. When not considering a document to be atomic but rather structured, more flexible access mechanisms to documents are possible [6, 11, 8]. Next to documents classification by subject, a traditional task of publishers and libraries, structured information can be used to locate and retrieve documents more effectively. For example, it is possible to retrieve only the abstract of full text documents, to retrieve all chapter ....

....their internal structure is advantageous with regard to the various services offered by digital libraries. Within our database application framework documents of arbitrary types can be handled. Querying documents according to their structure is an issue currently attracting researchers attention [6, 11, 8]. The queries given there can also be formulated using the VODAK Query Language VQL. Some sample queries Amsterdam Parser (ASP) Knowledge Bases DFRArchive VODAK DBMS Query Processing specific general INQUERY SGML Database Application external documents A2 A1 A1 B sample applications such as ....

G.E. Blake et al. Text / relational database management systems: Harmonizing sql and sgml. In Proceedings of the First International Conference on Applications of Databases. Lecture Notes in Computer Science, Springer Verlag, June 1994.

....access to attribute values in a page at the adm level, to physical access to text in the HTML source. The natural candidate to write wrappers for HTML documents seemed at first to be context free grammar parsers. These have in fact been used with success in other, more controlled frameworks [17, 26]. Unfortunately, we soon realized that HTML pages are far too complex to be captured by ordinary parsers. In fact, although sites have often a rather tight logical structure i.e. pages can be easily split in homogeneous sets, all pages in a set having essentially the same attributes they are ....

G. E. Blake, M. P. Consens, P. Kilpelainen, P. Larson, T. Snider, and F. W. Tompa. Text/relational database management systems: Harmonizing SQL and SGML. In First Intern. Conf. on Applications of Databases, (ADB'94), Vadstena, Sweden. LNCS 819, pages 267--280. Springer-Verlag, June 1994.

....provides query element independence. 4. 3 Related Work Work in the area of structured text retrieval generally either extends the relational algebra with support for structured text, uses a context free grammar to describe text structure and bases queries on this grammar, or attempts both [1, 2, 6, 7, 8]. This heavy dependence on relations and or grammars to describe text structure and formulate queries is in direct contrast to our work. GCL owes some of its intellectual and cultural heritage to two earlier structured text retrieval languages developed at the University of Waterloo. The Pat text ....

....of on line data is currently in the form of SQL relations. A simple representation of a SQL relation as a marked up sequence is sufficient to permit searching of an SQL database using GCL. This is particularly useful if inclusion of full text data in relational databases becomes more prevalent [1, 2]. We treat the data in a table as if loaded sequentially in row major order. The extent of each table is considered to be tagged with table and table tags. The name of the table is indexed immediately following the table start tag and is delineated with table name and table name ....

G. E. Blake, M. P. Consens, P. Kilpelainen, P.- A. Larson, T. Snider, and F. W. Tompa. Text/relational database management systems --- harmonizing SQL and SGML. In Proc. Applications of Databases, pages 267-- 280, Vadstena, Sweden, June 1994.

....whereas the operations are defined in the conventional database model. This also complicates the design of user interfaces for document management. A different approach to the integration of text and relational data is to extend the set of operators in SQL to accommodate structured text [6, 8, 18]. It is not based on transformations between documents and relational databases, but on the coexistence of data repositories for two types of data and the definition of a combined query language for them. Unlike in other approaches, the text remains intact as the authoritative repository of text ....

G.E. Blake, M.P. Consens, P. Kilpeläinen, P.-Å. Larson, T. Snider, and F.W. Tompa. Text / relational database management systems: harmonizing SQL and SGML. In Proc. Applications of Databases (ADB94) , pp. 267-280, Vadstena, Sweden (1994).

....provides query element independence. 4. 3 Related Work Work in the area of structured text retrieval generally either extends the relational algebra with support for structured text, uses a contextfree grammar to describe text structure and bases queries on this grammar, or attempts both [1, 2, 5, 8, 9, 10, 12, 14]. This heavy dependence on relations and or grammars to describe text structure and formulate queries is in direct contrast to our work. GCL owes some of its intellectual and cultural heritage to two earlier structured text retrieval languages developed at the University of Waterloo. The Pat text ....

....of on line data is currently in the form of SQL relations. A simple representation of a SQL relation as a marked up sequence is sufficient to permit searching of an SQL database using GCL. This is particularly useful if inclusion of full text data in relational databases becomes more prevalent [1, 2]. We treat the data in a table as if loaded Clarke, Cormack and Burkowski CCB = all of ( clarke , cormack , burkowski ) AUTHORS = name authors value . value CCB AUTHORS = CCB contained in AUTHORS TABLE = table . table REPORTS = table name reports table name REPTABLE ....

G. E. Blake, M. P. Consens, P. Kilpelainen, P.- A. Larson, T. Snider, and F. W. Tompa. Text/relational database management systems --- Harmonizing SQL and SGML. In Proc. Applications of Databases, pages 267--280, Vadstena, Sweden, June 1994.

.... combining grammar based data definition capabilities with operational capabilities on trees have also been introduced; consider, for example, the models of Gonnet and Tompa (1987) Furuta and Stotts (1988) Gyssens, Paredaens and Van Gucht (1989) Macleod (1990, 1991) Christophides (1994) and Blake et al. 1994). In fact, some of these models are hybrid models: text structure is defined by a grammar but the text operations may also be applied to text having no explicit grammar. The p string model (Gonnet Tompa 1987, Blake, Bray Tompa 1992) the model of Gyssens et al. 1989) A. Salminen and F. W. ....

Blake, G.E., Consens, M.P., Kilpelinen, P., Larson, P.-A., Snider, T., and Tompa, F.W., Text / relational database management systems: harmonizing SQL and SGML, Proc. Applications of Databases (ADB-94), Vadstena, June 1994, 267-280.

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G. E. Blake, M. P. Consens, P. Kilpelainen, P.- A. Larson, T. Snider, and F. W. Tompa. Text / relational database management systems: Harmonizing SQL and SGML. In Applications of Databases (Proceedings of the ADB'94 Conference), pages 267--280. Springer-Verlag Lecture Notes in Computer Science Nr. 819, 1994.

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G. E. Blake, M. P. Consens, P. Kilpelainen, P. Larson, T. Snider, and F. W. Tompa. Text/relational database management systems: Harmonizing SQL and SGML. In First Intern. Conf. on Applications of Databases, (ADB'94), Vadstena, Sweden. LNCS 819, pages 267--280. Springer-Verlag, June 1994.

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G. Blake, M. Consens, P. Kilpelainen, P. Larson, T. Snider, and F. Tompa. Text/relational database management systems: Harmonizing SQL and SGML. In Proceedings of the First International Conference on Applications of Databases, pages 267--280, Vadstena, Sweden, 1994.

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G.E. Blake et al. Text / Relational Database Management Systems: Harmonizing SQL and SGML. In Proceedings of the First International Conference on Applications of Databases. Lecture Notes in Computer Science, Springer Verlag, June 1994.

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G. Blake, M. Consens, P. Kilpelainen, P. Larson, T. Snider, and F. Tompa. Text/relational database management systems: Harmonizing SQL and SGML. In Proceedings of the First International Conference on Applications of Databases, pages 267--280, Vadstena, Sweden, 1994.

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G.E. Blake, M.P. Consens, P. Kilpelainen, P.- A. Larson, T. Snider, and F.W. Tompa. Text / Relational Database Management Systems: Harmonizing SQL and SGML. In Proceedings of the First International Conference on Applications of Databases, Lecture Notes in Computer Science. Springer Verlag, June 1994.

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G. Blake, M. Consens, P. Kilpelainen, P. Larson, T. Snider, and F. Tompa. Text / relational database management systems: Harmonizing SQL and SGML. In W. Litwin and T. Risch, editors, Applications of Databases: First International Conference, pages 267--280. Vadstena, Sweden, 1994.

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G. Blake, M. Consens, P. Kilpelainen, P. Larson, T. Snider, and F. Tompa. Text / relational database management systems: Harmonizing SQL and SGML. In W. Litwin and T. Risch, editors, Applications of Databases: First International Conference, pages 267--280. Vadstena, Sweden, 1994.

No context found.

G. Blake, M. Consens, P. Kilpelainen, P. Larson, T. Snider, and F. Tompa. Text/relational database management systems: Harmonizing SQL and SGML. In Proceedings of the First International Conference on Applications of Databases, pages 267--280, Vadstena, Sweden, 1994.

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