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Proceedings of 1994 IEEE 10th International Conference on Data Engineering

14-18 Feb. 1994

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  • Proceedings of 1994 IEEE 10th International Conference on Data Engineering

    Publication Year: 1994
    Request permission for commercial reuse | PDF file iconPDF (82 KB)
    Freely Available from IEEE
  • Analysis of common subexpression exploitation models in multiple-query processing

    Publication Year: 1994, Page(s):488 - 497
    Cited by:  Papers (2)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (748 KB)

    In multiple-query processing, a subexpression that appears in more than one query is called a common subexpression (CSE). A CSE needs to he evaluated once only to produce a temporary result that can then be used to evaluate all the queries containing the CSE. Therefore, the cost of evaluating the CSE is amortized over the queries requiring its evaluation. Two queries, posed simultaneously to the o... View full abstract»

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  • Capturing design dynamics - the CONCORD approach

    Publication Year: 1994, Page(s):440 - 451
    Cited by:  Papers (1)  |  Patents (1)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (1452 KB)

    `Computer-Supported Cooperative Work' is a young research area considering applications with strong demands on database technology. Design applications need support for cooperation and some means for controlling their inherent dynamics. However, today's CAD systems consisting of a collection of diverse design tools typically do not support these requirements. Therefore, an encompassing processing ... View full abstract»

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  • Sort-merge-join: an idea whose time has(h) passed?

    Publication Year: 1994, Page(s):406 - 417
    Cited by:  Papers (7)  |  Patents (3)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (1048 KB)

    Matching two sets of data items is a fundamental operation required in relational, extensible, and object-oriented database systems alike. However, the pros and cons of sort- and hash-based query evaluation techniques in modern query processing systems are still not fully understood. After our earlier research clarified strengths and weaknesses of sort- and hash-based query processing techniques a... View full abstract»

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  • A query sampling method for estimating local cost parameters in a multidatabase system

    Publication Year: 1994, Page(s):144 - 153
    Cited by:  Papers (14)  |  Patents (1)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (732 KB)

    In a multidatabase system (MDBS), some query optimization information related to local database systems may not be available at the global level because of local autonomy. To perform global query optimization, a method is required to derive the necessary local information. This paper presents a new method that employs a query sampling technique to estimate the cost parameters of an autonomous loca... View full abstract»

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  • Semantics-based multilevel transaction management in federated systems

    Publication Year: 1994, Page(s):452 - 461
    Cited by:  Papers (7)  |  Patents (3)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (844 KB)

    A federated database management system (FDBMS) is a special type of distributed database system that enables existing local databases, in a heterogeneous environment, to maintain a high degree of autonomy. One of the key problems in this setting is the coexistence of local transactions and global transactions, where the latter access and manipulate data of multiple local databases. In modeling FDB... View full abstract»

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  • Exploiting uniqueness in query optimization

    Publication Year: 1994, Page(s):68 - 79
    Cited by:  Papers (2)  |  Patents (9)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (924 KB)

    Consider an SQL query that specifies duplicate elimination via a DISTINCT clause. Because duplicate elimination often requires an expensive sort of the query result, it is often worthwhile to identify unnecessary DISTINCT clauses and avoid the sort altogether. We prove a necessary and sufficient condition for deciding if a query requires duplicate elimination. The condition exploits knowledge abou... View full abstract»

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  • Index structures for information filtering under the vector space model

    Publication Year: 1994, Page(s):337 - 347
    Cited by:  Papers (14)  |  Patents (2)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (792 KB)

    The authors study what data structures and algorithms can be used to efficiently perform large-scale information filtering under the vector space model, a retrieval model established as being effective. They apply the idea of the standard inverted index to index user profiles. They devise an alternative to the standard inverted index, in which they, instead of indexing every term in a profile, sel... View full abstract»

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  • Parallel approaches to database management

    Publication Year: 1994
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (28 KB)

    Abstract only given, as follows. A variety of parallel approaches have been used to support database processing across a spectrum of machine architectures. We begin by describing areas where parallelism is potentially important in dealing with very large databases, including loading, query/update, and database administration. We then discuss hardware tradeoffs, including multicomputers versus mult... View full abstract»

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  • Analysis of reorganization overhead in log-structured file systems

    Publication Year: 1994, Page(s):102 - 110
    Cited by:  Papers (5)  |  Patents (1)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (608 KB)

    In a log-structured file system (LFS), in general each block written to disk causes another disk block to become invalid data, resulting in one block of free space. Over time free disk space becomes highly fragmented, and a high level of dynamic reorganization may be required to coalesce free blocks into physically contiguous areas that subsequently can be used for logs. By consuming available dis... View full abstract»

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  • On the selection of optimal index configuration in OO databases

    Publication Year: 1994, Page(s):526 - 537
    Cited by:  Papers (5)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (1076 KB)

    An operation in object-oriented databases gives rise to the processing of a path. Several database operations may result into the same path. The authors address the problem of optimal index configuration for a single path. As it is shown an optimal index configuration for a path can be achieved by splitting the path into subpaths and by indexing each subpath with the optimal index organization. Th... View full abstract»

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  • Implementing calendars and temporal rules in next generation databases

    Publication Year: 1994, Page(s):264 - 273
    Cited by:  Papers (20)  |  Patents (1)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (716 KB)

    In applications like financial trading, scheduling, manufacturing and process control, time based predicates in queries and rules are very important. There is also a need to define lists of time points or intervals. The authors refer to these lists as calendars. The authors present a system of calendars that allow specification of natural-language time-based expressions, maintenance of valid time ... View full abstract»

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  • On a more realistic lock contention model and its analysis

    Publication Year: 1994, Page(s):2 - 9
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (640 KB)

    Most performance modeling studies of lock contention in transaction processing systems are deficient in that they postulate a homogeneous database access model. The non-homogeneous database access model described in this paper allows multiple transaction classes with different access patterns to the database regions. The performance of the system from the viewpoint of lock contention is analyzed i... View full abstract»

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  • Query optimization strategies for browsing sessions

    Publication Year: 1994, Page(s):478 - 487
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (680 KB)

    This paper describes techniques and experimental results to obtain response time improvement for a browsing session, i.e. a sequence of interrelated queries to locate a subset of interest. The optimization technique exploits symbolic analysis of the query interdependencies and retention of (partial) query answers. A prototype browsing session optimizer (BSO) has been constructed that runs as a fro... View full abstract»

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  • Fast ranking in limited space

    Publication Year: 1994, Page(s):428 - 437
    Cited by:  Patents (1)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (744 KB)

    Ranking techniques have long been suggested as alternatives to conventional Boolean methods for searching document collections. The cost of computing a ranking is, however, greater than the cost of performing a Boolean search, in terms of both memory space and processing time. The authors consider the resources required by the cosine method of ranking, and show that, with a careful application of ... View full abstract»

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  • Managing change in the Rufus system

    Publication Year: 1994, Page(s):170 - 179
    Cited by:  Papers (2)  |  Patents (1)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (824 KB)

    Rufus is an information system that models user data with objects taken from a class system. Due to the importance of coping with changes to the schema, Rufus has adopted the conformity-based model of Melampus. This model enables Rufus to cope with schema changes more easily than traditional class- and inheritance-based data models. The paper reviews the Melampus data model and describes how it wa... View full abstract»

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  • Performance evaluation of grid based multi-attribute record declustering methods

    Publication Year: 1994, Page(s):356 - 365
    Cited by:  Papers (2)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (680 KB)

    We focus on multi-attribute declustering methods which are based on some type of grid-based partitioning of the data space. Theoretical results are derived which show that no declustering method can be strictly optimal for range queries if the number of disks is greater than 5. A detailed performance evaluation is carried out to see how various declustering schemes perform under a wide range of qu... View full abstract»

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  • A multi-set extended relational algebra: a formal approach to a practical issue

    Publication Year: 1994, Page(s):80 - 88
    Cited by:  Papers (11)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (592 KB)

    The relational data model is based on sets of tuples, i.e. it does not allow duplicate tuples an a relation. Many database languages and systems do require multi-set semantics though, either because of functional requirements or because of the high costs of duplicate removal in database operations. Several proposals have been presented that discuss multi-set semantics. As these proposals tend to b... View full abstract»

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  • Efficient evaluation of the valid-time natural join

    Publication Year: 1994, Page(s):282 - 292
    Cited by:  Papers (24)  |  Patents (1)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (988 KB)

    Joins are arguably the most important relational operators. Poor implementations are tantamount to computing the Cartesian product of the input relations. In a temporal database, the problem is more acute for two reasons. First, conventional techniques are designed for the optimization of joins with equality predicates, rather than the inequality predicates prevalent in valid-time queries. Second,... View full abstract»

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  • Supporting data mining of large databases by visual feedback queries

    Publication Year: 1994, Page(s):302 - 313
    Cited by:  Papers (17)  |  Patents (3)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (1628 KB)

    Describes a query system that provides visual relevance feedback in querying large databases. The goal is to support the process of data mining by representing as many data items as possible on the display. By arranging and coloring the data items as pixels according to their relevance for the query, the user gets a visual impression of the resulting data set. Using an interactive query interface,... View full abstract»

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  • Efficient organization of large multidimensional arrays

    Publication Year: 1994, Page(s):328 - 336
    Cited by:  Papers (66)  |  Patents (7)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (640 KB)

    Large multidimensional arrays are widely used in scientific and engineering database applications. The authors present methods of organizing arrays to make their access on secondary and tertiary memory devices fast and efficient. They have developed four techniques for doing this: (1) storing the array in multidimensional “chunks” to minimize the number of blocks fetched, (2) reorderin... View full abstract»

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  • Discovering database summaries through refinements of fuzzy hypotheses

    Publication Year: 1994, Page(s):223 - 230
    Cited by:  Papers (2)  |  Patents (1)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (532 KB)

    Recently, many applications such as scientific databases and decision supporting systems that require comprehensive analysis of a very large amount of data, have been evolved. Summary discovery techniques, which extract compact representations grasping the meanings of large databases, can play a major role in those applications. We present an effective and robust method to discover simple linguist... View full abstract»

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  • Transactional workflows: research, enabling technologies and applications

    Publication Year: 1994
    Cited by:  Papers (9)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (36 KB)

    Abstract only given, as follows. Need to increase productivity and reduce cost have lead to reengineering and automation of operations across corporations. Some of the applications involve imaging, document processing and routing. These tasks can be effectively automated using current genre of workflow automation products. Some other applications involve tasks that can be modeled in client-server ... View full abstract»

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  • Performance analysis of RAIDS disk arrays with a vacationing server model for rebuild mode operation

    Publication Year: 1994, Page(s):111 - 119
    Cited by:  Papers (14)  |  Patents (1)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (752 KB)

    We analyze the performance of RAIDS disk arrays in normal, degraded, and rebuild modes. The analysis, which is shown to be highly accurate through validation against simulation results, achieves its accuracy by (1) modeling detailed disk characteristics; (2) developing a simple approximation to compute the mean response time for fork-join requests arising in degraded mode operation; and (3) using ... View full abstract»

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  • Applying signatures for forward traversal query processing in object-oriented databases

    Publication Year: 1994, Page(s):518 - 525
    Cited by:  Papers (10)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (480 KB)

    Forward traversal methods are used to process queries having nested predicates in object-oriented databases. To expedite the forward traversal, a signature replication technique is proposed. Object signature is a signature formed by values of all atomic attributes defined in the object. When an object refers to other objects through its attribute, the object signature of the referred object is sto... View full abstract»

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