Reasoning About the Updatability of XML Views Over Relational Databases

XML has become an important medium for data exchange, and is also used as an interface to – i.e. a view of – a relational database. While previous work has considered XML views for the purpose of querying relational databases (e.g. Silkroute), in this paper we consider the problem of updating a relational database through an XML view. Using the nested relational algebra as the formalism for an XML view of a relational database, we study the problem of when such views are updatable. Our results rely on the observation that in many XML views of relational databases, the nest operator occurs last and the unnest operator does not occur at all. Since in this case the nest operator is invertible, we can consider this important class of XML views as if they were flat relational views.

[1]  Hans-Jörg Schek,et al.  Remarks on the algebra of non first normal form relations , 1982, PODS.

[2]  Umeshwar Dayal,et al.  On the correct translation of update operations on relational views , 1982, TODS.

[3]  Umeshwar Dayal,et al.  On the Updatability of Relational Views , 1978, VLDB.

[4]  Antonio L. Furtado,et al.  A Pragmatic Approach to Structured Database Design , 1983, VLDB.

[5]  David W. Embley,et al.  A normal form for precisely characterizing redundancy in nested relations , 1996, TODS.

[6]  Frank Wm. Tompa,et al.  Understanding the implications of view update policies , 1985, Algorithmica.

[7]  Guy Hulin.  On Restructuring Nested Relations in Partitioned Normal Form , 1990, VLDB.

[8]  Akifumi Makinouchi,et al.  A Consideration on Normal Form of Not-Necessarily-Normalized Relation in the Relational Data Model , 1977, VLDB.

[9]  Arthur M. Keller,et al.  Algorithms for translating view updates to database updates for views involving selections, projections, and joins , 1985, PODS.

[10]  Gio Wiederhold,et al.  Penguin: Objects for Programs, Relations for Persistence , 1999 .

[11]  H. Shu.  Using Constraint Satisfaction for View Update Translation , 1998, ECAI.

[12]  Antonio L. Furtado,et al.  Permitting updates through views of data bases , 1979, Inf. Syst..

[13]  Rom Langerak,et al.  View updates in relational databases with an independent scheme , 1990, TODS.

[14]  Antonio L. Furtado,et al.  Updating Relational Views , 1985, Query Processing in Database Systems.

[15]  Serge Abiteboul,et al.  Non first normal form relations to represent hierarchically organized data , 1984, PODS.

[16]  Umeshwar Dayal,et al.  On the updatability of network views-extending relational view theory to the network model , 1982, Inf. Syst..

[17]  Dan Suciu,et al.  SilkRoute: trading between relations and XML , 2000, Comput. Networks.

[18]  Arthur M. Keller,et al.  The Role of Semantics in Translating View Updates , 1986, Computer.

[19]  David W. Embley,et al.  Using Nested Tables for Representing and Querying Semistructured Web Data , 2002, CAiSE.

[20]  Marcelo Arenas,et al.  A normal form for XML documents , 2004, TODS.

[21]  Lawrence A. Rowe,et al.  Data abstraction, views and updates in RIGEL , 1979, SIGMOD '79.

[22]  Gio Wiederhold,et al.  Updating relational databases through object-based views , 1991, SIGMOD '91.

[23]  David W. Embley,et al.  Representing and Querying Semistructured Web Data Using Nested Tables with Structural Variants , 2002, ER.

[24]  Nicolas Spyratos,et al.  Update semantics of relational views , 1981, TODS.

[25]  Patrick C. Fischer,et al.  Nested Relational Structures , 1986, Adv. Comput. Res..