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Purpose - The purpose of this paper is to compare the use of two Object-Relational models against the use of a post-Relational model for a realistic application. Although real-world applications, in most cases, can be adequately m...
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Purpose - The purpose of this paper is to compare the use of two Object-Relational models against the use of a post-Relational model for a realistic application. Although real-world applications, in most cases, can be adequately modeled by the Entity-Relationship (ER) model, the transformation to the popular Relational model alters the representation of structures common in reality, like multi-valued and composite fields. Alternative database models have been developed to overcome these shortcomings. Design/methodology/approach - Based on the ER model of a medical application, this paper compares the information representation, manipulation and enforcement of integrity constraints through PostgreSQL and Oracle, against the use of a post-Relational model composed of the Conceptual Universal Database Language (CUDL) and the Conceptual Universal Database Language Abstraction Level (CAL). Findings - The CAL/CUDL pair, although more periphrastic for data definition, is simpler for data insertions, does not require the use of procedural code for data updates, produces clearer output for retrieval of attributes, can accomplish retrieval of rows based on conditions that address composite data with declarative statements and supports data validation for relationships between composite data without the need for procedural code. Research limitations/implications - To verify, in practice, the conclusions of the paper, complete implementation of a CAL/CUDL system is needed. Practical implications - The use of the CAL/CUDL pair would advance the productivity of database application development. Originality/value - This paper highlights the properties of realistic database-applications modelling and management that are desirable by developers and shows that these properties are better satisfied by the CAL/CUDL pair.
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In this paper, we present methods of translating transactions from object-oriented database (OODB) to relational database (RDB). The process involves schema mapping in data definition language and transaction translation in data m...
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In this paper, we present methods of translating transactions from object-oriented database (OODB) to relational database (RDB). The process involves schema mapping in data definition language and transaction translation in data manipulation language. They include scheme definition, data query and transaction operation of insert, update, and deletion. We also discuss the object-oriented features in OODB operations that are not supported by RDB, such as class hierarchy, class composition hierarchy, and set attribute, and provide a general solution to realize those mechanisms by traditional relation operations. The result of the transaction translation can be applied into adding object-oriented interface into relational database management system and to the interoperability between OODB and RDB.
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Motion capture data have been widely used in applications ranging from video games and animations to simulations and virtual environments. Moreover, all data-driven approaches for analysis and synthesis of motions are depending on...
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Motion capture data have been widely used in applications ranging from video games and animations to simulations and virtual environments. Moreover, all data-driven approaches for analysis and synthesis of motions are depending on motion capture data. Although multiple large motion capture datasets are freely available for research, there is no system which can provide a centralised access to all of them in an organised manner. In this paper, we show that using a relational database management system (RDBMS) to store data not only provide such a centralised access to the data, but also allows to include other sensor modalities (e.g., accelerometer data) and various semantic annotations. We present two applications for our system: a motion capture player where motions sequences can be retrieved from large datasets using SQL queries and the automatic construction of statistical models which can further be used for complex motion analysis and motions synthesis tasks.
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Object-relational technology provides a significant increase in scalability and flexibility over the traditional relational databases. The additional object-relational features are particularly satisfying for advanced database app...
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Object-relational technology provides a significant increase in scalability and flexibility over the traditional relational databases. The additional object-relational features are particularly satisfying for advanced database applications that relational database systems have experienced difficulties. The key factor to the success of object-relational database systems is their performance. This paper aims to review the promises of Object-Relational database systems, examine the reality, and how their promises may be fulfilled through unification with the relational technology. To investigate the performance implications of using object-relational relative to relational technology, the query-oriented BUCKY benchmark has been previously applied to an early object-relational database system, i.e., Illustra 97. This paper presents the results obtained from implementing and running the BUCKY benchmark on Oracle 10g. The results acquired from the work described in this paper are compared with the results obtained in BUCKY benchmark This study throws light on the functionality of object-relational databases, where object-relational technology has made improvements but some limitations are identified as well. In general, the performance of relational supersedes that of object-relational database system.
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The article deals with Codd's relational model of data and its fuzzy logic extensions. Our main purpose is to examine, from the point of view of fuzzy logic in the narrow sense, some of the extensions proposed in the literature an...
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The article deals with Codd's relational model of data and its fuzzy logic extensions. Our main purpose is to examine, from the point of view of fuzzy logic in the narrow sense, some of the extensions proposed in the literature and the relationships between them. We argue that fuzzy logic in the narrow sense is important for the fuzzy logic extensions because it provides conceptual and methodological foundations, clarity and simplicity. We present several comparative observations as well as new technical results.
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A relational database D is given with Q as the set of attributes. We assume that the rows (tuples, data of one individual) are transmitted through a noisy channel (or, as many times in case of the data mining applications, the obs...
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A relational database D is given with Q as the set of attributes. We assume that the rows (tuples, data of one individual) are transmitted through a noisy channel (or, as many times in case of the data mining applications, the observed data is distorted from the real values in a manner which we cannot know). In case of low probability of the error it may be supposed that at most one data in a row is changed by the transmission or observation. We say that A -> b (A subset of Omega, b epsilon Omega) is an error-correcting functional dependency if the data in A uniquely determine the data in b in spite of this error. We investigate the problem how much larger a minimal error-correcting functional dependency can be than the original one. We will give upper and lower bounds showing that it can be considerably larger than the original sizes, but the growth is only polynomial. (C) 2007 Elsevier B.V. All rights reserved.
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The problems with cataloguing and categorising heterogeneous resources on the World Wide Web for retrieving precise information are discussed. By providing a database approach to the Web site, these problems can be solved to some ...
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The problems with cataloguing and categorising heterogeneous resources on the World Wide Web for retrieving precise information are discussed. By providing a database approach to the Web site, these problems can be solved to some extent. The design isdone for software in biotechnology and bioengineering. The data about bio software on the Web are collected and arranged in a generalised standard format. These are loaded on to a MYSQL database and are accessed through Practical Extraction and Reporting Language (PERL) script. An attempt has also been made to study the search and memory allocation performance for the following databases: MYSQL, World Wide Web Integrated Set Of Information System (WWWISIS), and Managing Gigabytes (MG).
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Qian and Wiederhold (1991) presented an algorithm for the incremental recomputation of relational algebra expressions that was claimed to preserve a certain minimality condition. This condition guarantees that the incremental chan...
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Qian and Wiederhold (1991) presented an algorithm for the incremental recomputation of relational algebra expressions that was claimed to preserve a certain minimality condition. This condition guarantees that the incremental change sets do not contain any unnecessary tuples; so, redundant computations are not performed. We show that, in fact, their algorithm violates this condition. We present an improved algorithm that does preserve this notion of minimality.
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A combinatorial, data-oriented approach is suggested to study generalized relational databases (GRDs) and generalized functional dependencies (GFDs). GRDs, as denned here, extend the traditional relational model by Codd. Also, cer...
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A combinatorial, data-oriented approach is suggested to study generalized relational databases (GRDs) and generalized functional dependencies (GFDs). GRDs, as denned here, extend the traditional relational model by Codd. Also, certain aspects of nonfirst-normal-form databases and databases with null values can be captured in the setting of GRDs. We show that, after a suitable transformation, GPDs can be described in the framework of traditional functional dependencies (FDs). This leads to a convenient description of GFDs in terms of prepositional logic.
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k-Anonymity protects privacy by ensuring that data cannot be linked to a single individual. In a k-anonymous data set, any identifying information occurs in at least k tuples. Much research has been done to modify a single-table d...
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k-Anonymity protects privacy by ensuring that data cannot be linked to a single individual. In a k-anonymous data set, any identifying information occurs in at least k tuples. Much research has been done to modify a single-table data set to satisfy anonymity constraints. This paper extends the definitions of k-anonymity to multiple relations and shows that previously proposed methodologies either fail to protect privacy or overly reduce the utility of the data in a multiple relation setting. We also propose two new clustering algorithms to achieve multirelational anonymity. Experiments show the effectiveness of the approach in terms of utility and efficiency.
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