Relational DBMS typically execute concurrent queries independently by invoking a set of operator instances for each query. To exploit common data retrievals and computation in concurrent queries, researchers have proposed a wealth of techniques, ranging from buffering disk pages to constructing materialized views and optimizing multiple queries. The ideas proposed, however, are inherently limited by the query-centric philosophy of modern engine designs. Ideally, the query engine should proactively coordinate same-operator execution among concurrent queries, thereby exploiting common accesses to memory and disks as well as common intermediate result computation.

Abstract. Web Service Technology develops rapidly as it provides flexible application to application interaction mechanism. Much preliminary work has been done in various aspects of web service technology, including the modeling, specification, discovery, composition and verification of web services. One way of deciding the relative relevance of the various research directions is to look at their applicability to the currently available web services. To this end, we took a snapshot of the currently publicly available web services. Our aim is to get an idea of the number, type and complexity of these web services and see if this analysis provides useful information about the near-term fruitful research directions. 1

More than two decades ago, DB researchers faced up to the question of how to design a data-independent database management system (DBMS), that is, a DBMS which offers an appropriate application programming interface (API) to the user and whose architecture is open for permanent evolution. For this purpose, an architectural model based on successive data abstraction steps of record-oriented data was proposed as kind of a standard and later refined to a five-layer hierarchical DBMS model. We review the basic concepts and implementation techniques of this model and survey the major improvements achieved in the system layers to date. Furthermore, we consider the interplay of the layered model with the transactional ACID properties and again outline the progress obtained. In the course of the last 20 years, this DBMS architecture was challenged by a variety of new requirements and changes as far as processing environments, data types, functional extensions, heterogeneity, autonomy, scalability, etc. are concerned. We identify the cases which can be adjusted by our standard system model and which need major extensions or other types of system models.

We show how new syntactic forms and static analysis can be added to a programming language to support abstractions provided by libraries. Libraries have the important characteristic that programmers can use multiple libraries in a single program. Thus, any attempt to extend a language’s syntax and analysis should be done in a composable manner so that similar extensions that support other libraries can be used by the programmer in the same program. To accomplish this we have developed an extensible attribute grammar specification of Java 1.4 written in the attribute grammar specification language Silver. Library writers can specify, as an attribute grammar, new syntax and analysis that extends the language and supports their library. The Silver tools automatically compose the grammars defining the language and the programmer-selected language extensions (for their chosen libraries) into a specification for a new custom language that has language-level support for the libraries. We demonstrate how syntax and analysis are added to a language by extending Java with syntax from the query language SQL and static analysis of these constructs so that syntax and type errors in SQL queries can be detected at compile-time. 1.

Neighborhood Interchangeability (NI) identifies the equivalent values in the domain of a variable in a Constraint Satisfaction Problem (CSP). We introduce for the first time an algorithm for computing NI sets in the presence of non-binary constraints. We integrate this mechanism with backtrack search, in a process we call dynamic bundling. We demonstrate that, as for the binary case [Beckwith et al., 2001], dynamic bundling yields multiple robust solutions for less effort than necessary for computing a single solution. We then identify the utility of this mechanism for database applications and introduce a new algorithm based on dynamic bundling for computing a join query, which we model as a CSP. We argue that the algorithm yields a compact solution space and saves memory, disk-space, and/or network bandwidth. Finally, we discuss the application of the join algorithm to materialize views. ACKNOWLEDGEMENTS I would like to thank my advisor, Professor Berthe Y. Choueiry, for her tireless support and guidance since the beginning of this research. Without her help this work would not have been possible. I would like to thank my committee members, Professors Matthew

While information retrieval (IR) and databases (DB) have been developed independently, there have been emerging requirements that both data management and efficient text retrieval should be supported simultaneously in an information system such as health care systems, bulletin boards, XML data management, and digital libraries. Recently DB-IR integration issue has been budded in the research field. The great divide between DB and IR has caused different manners in index maintenance for newly arriving documents. While DB has extended its SQL layer to cope with text fields due to lack of intact mechanism to build IR-like index, IR usually treats a block of new documents as a logical unit of index maintenance since it has no concept of integrity constraint. However, towards DB-IR integration, a transaction on adding or updating a document should include maintenance of the postings lists accompanied by the document – hence per-document basis transactional index maintenance. In this paper, performance of a few strategies for per-document basis transaction for inserting documents – direct index update, stand-alone auxiliary index and pulsing auxiliary index – will be evaluated. The result tested on the KRISTAL-IRMS shows that the pulsing auxiliary strategy, where long postings lists in the auxiliary index are in-place updated to the main index whereas short lists are directly updated in the auxiliary index, can be a challenging candidate for text field indexing in DB-IR integration.

We make the case for a sensor network model in which each mote stores sensor data locally, and provides a database query interface to the data. Unlike TinyDB and Cougar, in which a sink node provides a database-like front end for filtering the current sensor values from a data collection network, we propose that each sensor device should run its own database system. We present Antelope, a database management system for resource-constrained sensors. Antelope provides a dynamic database system that enables run-time creation and deletion of databases and indexes. Antelope uses energy-efficient indexing techniques that significantly improve the performance of queries. The energy cost of a query that selects 100 tuples is less than the cost of a single packet transmission. Moving forward, we believe that database techniques will be increasingly important in many emerging applications.

this paper, we present a control theoretic approach for a database to autonomously-without substantial human interventions for (re)tuning the database-control data conflicts by adjusting the multiprogramming level even when the workload varies dynamically. To apply control theoretic approaches, we mathematically model the relation between the multiprogramming level and data conflicts. Based on the model, a feedback control framework is developed to maintain data conflicts, if any, below the threshold. Admission control and transaction cancellation are applied to enforce the required multiprogramming level adjustment computed in the feedback loop, if necessary, to control data conflicts. In this way, data conflicts can be controlled to be below the threshold even when the system is under a transient state subject to substantial data conflicts. Hence, the availability of database service can be significantly improved

Column-oriented indexes—such as projection or bitmap indexes—are compressed by run-length encoding to reduce storage and increase speed. Sorting the tables improves compression. On realistic data sets, permuting the columns in the right order before sorting can reduce the number of runs by a factor of two or more. For many cases, we prove that the number of runs in table columns is minimized if we sort columns by increasing cardinality. Yet—maybe surprisingly—we must sometimes maximize the number of runs to minimize the index size. Experimentally, sorting based on Hilbert space-filling curves is poor at minimizing the number of runs. Key words:

Abstract. A focus of Grid computing are data intensive applications. Additionally, database management systems (DBMS) are gaining on importance in many scientific disciplines for publication of research results. The employment of Service-oriented-Architecture (SoA) raises the question of how DBMSs and their built-in technologies can be best utilized in such environments. A common way is to pull out all required data for a certain task from a source and process it service side far away from the original source. This approach is characterized by a passive usage of the DBMS as a pure data provider which implies significant overheads. The research effort described in this paper allows an active usage of a DBMS by relocating distributed query processing functionality inside it. Our novel solution utilizes the existing database technology, puts just the interface code at the service level while the data processing code resides at the database level and uses a push mechanism for the result data. The advantages are less overheads and data movement as well as increased data locality. Our proof of concept implementation is evaluated by comparing our distributed query processing prototype working inside popular relational DBMS (Oracle 10g and PostGreSQL 8.3) with a traditional installation of the OGSA-DQP middleware developed for distributed query processing on the Grid. 1