the proceedings contain 16 papers. the topics discussed include: efficient algorithms for the tree homeomorphism problem;a methodology for coupling fragments of XPath with structural indexes for XML documents;conjunct...
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ISBN:
(纸本)9783540759867
the proceedings contain 16 papers. the topics discussed include: efficient algorithms for the tree homeomorphism problem;a methodology for coupling fragments of XPath with structural indexes for XML documents;conjunctive query containment over trees;a better semantics for XQuery with side-effects;repairing inconsistent XML write-access control policies;on the consistent rewriting of conjunctive queries under primary key constraints;relational completeness of query languages for annotated databases;a theory of stream queries;querying structural and behavioral properties of business processes;succinctness of pattern-based schema languages for XML;analysis of imperative XML programs;efficient inclusion for a class of XML types with interleaving and counting;and towards practical typechecking for macro tree transducers.
Data variations are prevalent in real-world applications. For example, software vendors handle variations in the business requirements, conventions, and environmental settings of a software product using hundreds of f...
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ISBN:
(纸本)9781450353540
Data variations are prevalent in real-world applications. For example, software vendors handle variations in the business requirements, conventions, and environmental settings of a software product using hundreds of features each combination of which creates a different version of the product. In database-backed software, the database of each version may have a different schema and different content. Variations in the value and representation of each element in a dataset give rise to numerous variants in these applications. Users often would like to express information needs over all such variants. For example, a software vendor would like to perform common tests over all versions of its product, e.g., whether each relation in a relational database has a primary key. Hence, users need a query interface that hides the variational nature of the data and processes a query over all variations of a dataset. We propose a novel abstraction called a variational databasethat provides a compact and structured representation of general forms of data variations and enables users to query database variations easily.
Server-side execution is a well-known method for improving the performance of database applications. Running code on the database server eliminates round trips to the client application resulting in significantly redu...
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ISBN:
(纸本)9781450353540
Server-side execution is a well-known method for improving the performance of database applications. Running code on the database server eliminates round trips to the client application resulting in significantly reduced latency. However, the common approach of explicitly writing server-side code in stored procedures has significant drawbacks. Application developers must develop and maintain code in two separate languages and manually partition code between the client and server. Code shipping is a viable alternative but still requires an explicit specification of which code can be run on the server. We propose a hybrid shipping approach based on static analysis which automatically partitions client code and only ships code to the server which is likely to improve performance. We demonstrate the viability of this approach in a prototype system which we call Locomotor. Locomotor operates on Python applications using the Redis key-value store. through static analysis, it identifies fragments of code which can benefit from being executed on the server and automatically performs translation to execute the fragments on the server. Unlike some previous systems, Locomotor is not pattern-based and is able to ship a wide variety of code. By shipping code to the server, Locomotor is able to achieve significant performance gains over client-side execution with no modifications to the application code.
the proceedings contain 10 papers. the topics discussed include: modern stored procedures using GraalVM;bridging the semantical gap between relational data and application-level business objects with core data service...
ISBN:
(纸本)9781450353540
the proceedings contain 10 papers. the topics discussed include: modern stored procedures using GraalVM;bridging the semantical gap between relational data and application-level business objects with core data services;DDO-free XQuery;from relation algebra to semi-join algebra: an approach for graph query optimization;the data cube as a typed linear algebra operator;AL: unified analytics in domain specific terms;property-based testing of SPARQL queries;counting types for massive JSON datasets;locomotor: transparent migration of client-side database code;and GraphScript: implementing complex graph algorithms in SAP HANA.
this volume contains the proceedings of the 11thinternationalsymposium on databaseprogramminglanguages (dbpl 2007), held in Vienna, Austria, on September 23–24, 2007. dbpl 2007 was one of 15 meetings co-located w...
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ISBN:
(数字)9783540759874
ISBN:
(纸本)9783540759867
this volume contains the proceedings of the 11thinternationalsymposium on databaseprogramminglanguages (dbpl 2007), held in Vienna, Austria, on September 23–24, 2007. dbpl 2007 was one of 15 meetings co-located with VLDB (the international Conference on Very Large Data Bases). dbplcontinues to presentthe verybest workat the intersectionof database and programming language research. the proceedings include a paper based on the invited talk by Wenfei Fan and the 16 contributed papers that were selected by the programcommittee from 41 submissions. Every submission was reviewed by at least three members of the program committee. In addition, the program committee sought the opinions of additional referees, selected because of their expertise on particular topics. the ?nal selection of papers was made during the last week of July. We would like to thank all of the authors who submitted papers to the c- ference, and the members of the program committee for their excellent work. the program committee did not meet in person, but carried out extensive d- cussions during the electronic PC meeting. We are grateful to Andrei Voronkov for his EasyChair system that made it so easy to manage these discussions. Finally, we would also like to thank Christoph Koch and Gavin Bierman for their assistance and sound counsel, and the organizers of VLDB 2007 for taking care of the local organization of dbpl.
Provenance for database queries or scientific workflows is often motivated as providing explanation, increasing understanding of the underlying data sources and processes used to compute the query, and reproducibility...
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ISBN:
(纸本)9781450329477
Provenance for database queries or scientific workflows is often motivated as providing explanation, increasing understanding of the underlying data sources and processes used to compute the query, and reproducibility, the capability to recompute the results on different inputs, possibly specialized to a part of the output. Many provenance systems claim to provide such capabilities;however, most lack formal definitions or guarantees of these properties, while others provide formal guarantees only for relatively limited classes of changes. Building on recent work on provenance traces and slicing for functional programminglanguages, we introduce a detailed tracing model of provenance for multiset-valued Nested Relational Calculus, define trace slicing algorithms that extract subtraces needed to explain or recompute specific parts of the output, and define query slicing and differencing techniques that support explanation. We state and prove correctness properties for these techniques and present a proof-of-concept implementation in Haskell.
the paper develops EDITOR, a language for manipulating semistructured documents, such as those typically available on the Web. EDITOR programs are based on two simple ideas, taken from text editors: "search"...
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the paper develops EDITOR, a language for manipulating semistructured documents, such as those typically available on the Web. EDITOR programs are based on two simple ideas, taken from text editors: "search" instructions are used to select regions of interest in a document, and "cut & paste" instructions to restructure them. We study the expressive power and the complexity of these programs. We show that they are computationally complete, in the sense that any computable document restructuring can be expressed in EDITOR. We also study the complexity of a safe subclass of programs, showing that it captures exactly the class of polynomial-time restructurings. the language has been implemented in Java and is currently used in the ARANEUS project as a basis for a wrapper-generation toolkit. (C) 1999 Academic Press.
With motivation from considerations in XML databasetheory and model checking, data strings have been introduced as an extension of finite alphabet strings which carry, at each position, a symbol and a data value from...
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ISBN:
(纸本)9783540742395
With motivation from considerations in XML databasetheory and model checking, data strings have been introduced as an extension of finite alphabet strings which carry, at each position, a symbol and a data value from an infinite domain. Previous work has shown that it is difficult to come up with an expressive yet decidable automaton model for data languages. Recently, such a model, data automata, was introduced. this paper introduces a simpler but equivalent model and investigates its expressive power, algorithmic and closure properties, and some extensions. (C) 2009 Elsevier B.V. All rights reserved.
this paper presents a study about how different ways of representing meanings in programs can help in knowledge transfer of programming logic from a visual programming language to a textual programming language. these...
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the proceedings contain 4 papers. the topics discussed include: quantitative aspects of programminglanguages and systems over the past 2-4 years and beyond;towards digital twins for the description of automotive soft...
the proceedings contain 4 papers. the topics discussed include: quantitative aspects of programminglanguages and systems over the past 2-4 years and beyond;towards digital twins for the description of automotive software systems;a faster-than relation for semi-Markov decision processes;and probabilistic output analyses for deterministic programs â€" reusing existing non-probabilistic analyses.
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