The use of the Steiner tree (or the shortest connection) as a model for automatic logical navigation among relations is described. An efficient approximation algorithm is introduced for finding shortest connections. The model is extended to allow for ambiguous words in queries. The capability of this method is demonstrated by a simple database interface which is both easy to build and easy to use. The method can also be used in other query systems as a tool for finding navigation routes.<>
{"title":"Automated logical navigation among relations using Steiner trees","authors":"Dekang Lin","doi":"10.1109/ICDE.1989.47265","DOIUrl":"https://doi.org/10.1109/ICDE.1989.47265","url":null,"abstract":"The use of the Steiner tree (or the shortest connection) as a model for automatic logical navigation among relations is described. An efficient approximation algorithm is introduced for finding shortest connections. The model is extended to allow for ambiguous words in queries. The capability of this method is demonstrated by a simple database interface which is both easy to build and easy to use. The method can also be used in other query systems as a tool for finding navigation routes.<<ETX>>","PeriodicalId":329505,"journal":{"name":"[1989] Proceedings. Fifth International Conference on Data Engineering","volume":"181 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1989-02-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123189921","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The effectiveness of parallel processing of relational join operations is examined. The skew in the distribution of join attribute values and the stochastic nature of the task processing times are identified as the major factors that can affect the effective utilization of parallelism. When many small processors are used in the parallel architecture, the skew can result in some processors becoming sources of bottleneck while other processors are being under utilized. Even in the absence of skew, the variations in the processing times of the parallel tasks belonging to a query can lead to high task synchronization delay and impact the maximum speedup achievable through parallel execution. Analytic expressions for join execution time are developed for different task time distributions with or without skew.<>
{"title":"Limiting factors of join performance on parallel processors","authors":"M. Lakshmi, Philip S. Yu","doi":"10.1109/ICDE.1989.47254","DOIUrl":"https://doi.org/10.1109/ICDE.1989.47254","url":null,"abstract":"The effectiveness of parallel processing of relational join operations is examined. The skew in the distribution of join attribute values and the stochastic nature of the task processing times are identified as the major factors that can affect the effective utilization of parallelism. When many small processors are used in the parallel architecture, the skew can result in some processors becoming sources of bottleneck while other processors are being under utilized. Even in the absence of skew, the variations in the processing times of the parallel tasks belonging to a query can lead to high task synchronization delay and impact the maximum speedup achievable through parallel execution. Analytic expressions for join execution time are developed for different task time distributions with or without skew.<<ETX>>","PeriodicalId":329505,"journal":{"name":"[1989] Proceedings. Fifth International Conference on Data Engineering","volume":"41 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1989-02-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127432371","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
LINDA, an experimental system for database access in heterogeneous environments, is discussed. The goal is to achieve maximum site autonomy and as much database access homogenization as possible. The problems to be solved are discussed, and design priorities are justified. Major heterogeneity problems are sketched, and the applied techniques are briefly described. An overview of the implementation of the system is given, and the system's applicability is discussed.<>
{"title":"LINDA: a system for loosely integrated databases","authors":"A. Wolski","doi":"10.1109/ICDE.1989.47201","DOIUrl":"https://doi.org/10.1109/ICDE.1989.47201","url":null,"abstract":"LINDA, an experimental system for database access in heterogeneous environments, is discussed. The goal is to achieve maximum site autonomy and as much database access homogenization as possible. The problems to be solved are discussed, and design priorities are justified. Major heterogeneity problems are sketched, and the applied techniques are briefly described. An overview of the implementation of the system is given, and the system's applicability is discussed.<<ETX>>","PeriodicalId":329505,"journal":{"name":"[1989] Proceedings. Fifth International Conference on Data Engineering","volume":"65 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1989-02-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126054575","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Using the Application Development Toolkit (ADT) as an example, it is shown that by borrowing some techniques from the artificial-intelligence field, database-centered application-development productivity tools can be made more acceptable to end users and more useful to expert developers. Experience with ADT has indicated that a more end-user-oriented approach, and, in particular, more accommodating and application-oriented interface, is needed. A characteristic set of problems that are found in the class of productivity tools similar to ADT is presented. A series of possible improvements that shed some light on deficiencies in current state-of-the-art application-generation systems and productivity tools is suggested.<>
{"title":"Knowledge-based support for the development of database-centered applications","authors":"Hany M. Atchan, R. Bell, B. Thuraisingham","doi":"10.1109/ICDE.1989.47240","DOIUrl":"https://doi.org/10.1109/ICDE.1989.47240","url":null,"abstract":"Using the Application Development Toolkit (ADT) as an example, it is shown that by borrowing some techniques from the artificial-intelligence field, database-centered application-development productivity tools can be made more acceptable to end users and more useful to expert developers. Experience with ADT has indicated that a more end-user-oriented approach, and, in particular, more accommodating and application-oriented interface, is needed. A characteristic set of problems that are found in the class of productivity tools similar to ADT is presented. A series of possible improvements that shed some light on deficiencies in current state-of-the-art application-generation systems and productivity tools is suggested.<<ETX>>","PeriodicalId":329505,"journal":{"name":"[1989] Proceedings. Fifth International Conference on Data Engineering","volume":"30 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1989-02-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131122001","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
An approach is presented for integrating AI (artificial intelligence) systems with DBMS (database management systems). The impedance mismatch that has made this integration a problem is, in essence, a difference in the two system models of data processing. The present approach is to avoid the mismatch by forcing both AI systems and DBMS into the common model of stream processing. The approach taken in the Tangram project at UCLA, which integrates Prolog with relational DBMS, is described. Prolog is extended to a functional language called Log(F) that facilitates development of stream processing programs. The integration of this system with DBMS is simultaneously elegant, easy to use, and relatively efficient.<>
{"title":"Integrating AI and DBMS through stream processing","authors":"D. S. Parker","doi":"10.1109/ICDE.1989.47224","DOIUrl":"https://doi.org/10.1109/ICDE.1989.47224","url":null,"abstract":"An approach is presented for integrating AI (artificial intelligence) systems with DBMS (database management systems). The impedance mismatch that has made this integration a problem is, in essence, a difference in the two system models of data processing. The present approach is to avoid the mismatch by forcing both AI systems and DBMS into the common model of stream processing. The approach taken in the Tangram project at UCLA, which integrates Prolog with relational DBMS, is described. Prolog is extended to a functional language called Log(F) that facilitates development of stream processing programs. The integration of this system with DBMS is simultaneously elegant, easy to use, and relatively efficient.<<ETX>>","PeriodicalId":329505,"journal":{"name":"[1989] Proceedings. Fifth International Conference on Data Engineering","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1989-02-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127876492","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The quasi-partitioning paradigm of operation for partitioned database systems is discussed in which a broken main link between two partitions can be replaced by a much slower backup link (e.g. a dial-up telephone connection). The paradigm solves the problem of preparation for network partitioning. The quasi-partitioning mode of operation has two primitive operations: creeping retrieval and creeping merge. Creeping retrieval increases data availability by crossing partition boundaries (over backup links) to read foreign data. Similarly, creeping merge improves the degree of partition-consistency by crossing partition boundaries to perform merge actions. A quasi-partitioning protocol consists of an adaptation protocol and a merge protocol. Taxonomies are shown for quasi-partitioning adaptation protocols and for quasi-partitioning merge protocols (for restoring partition-consistency after system reconnection). Since merge protocols and adaptation protocols are interdependent, it is indicated here how these protocols should be paired.<>
{"title":"Quasi-partitioning: a new paradigm for transaction execution in partitioned distributed database systems","authors":"L. Lilien","doi":"10.1109/ICDE.1989.47261","DOIUrl":"https://doi.org/10.1109/ICDE.1989.47261","url":null,"abstract":"The quasi-partitioning paradigm of operation for partitioned database systems is discussed in which a broken main link between two partitions can be replaced by a much slower backup link (e.g. a dial-up telephone connection). The paradigm solves the problem of preparation for network partitioning. The quasi-partitioning mode of operation has two primitive operations: creeping retrieval and creeping merge. Creeping retrieval increases data availability by crossing partition boundaries (over backup links) to read foreign data. Similarly, creeping merge improves the degree of partition-consistency by crossing partition boundaries to perform merge actions. A quasi-partitioning protocol consists of an adaptation protocol and a merge protocol. Taxonomies are shown for quasi-partitioning adaptation protocols and for quasi-partitioning merge protocols (for restoring partition-consistency after system reconnection). Since merge protocols and adaptation protocols are interdependent, it is indicated here how these protocols should be paired.<<ETX>>","PeriodicalId":329505,"journal":{"name":"[1989] Proceedings. Fifth International Conference on Data Engineering","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1989-02-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128979977","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A password authentication mechanism based on the public-key distribution cryptosystem is proposed. The scheme uses an authentication table to replace the traditional password file. With this scheme, even if the authentication table is comprised, the system security is preserved. The user's password is effectively bound to the user's identification in a timely, efficient, and simple manner.<>
{"title":"Password authentication based on public-key distribution cryptosystem","authors":"L. Harn, D. Huang, C. Laih","doi":"10.1109/ICDE.1989.47233","DOIUrl":"https://doi.org/10.1109/ICDE.1989.47233","url":null,"abstract":"A password authentication mechanism based on the public-key distribution cryptosystem is proposed. The scheme uses an authentication table to replace the traditional password file. With this scheme, even if the authentication table is comprised, the system security is preserved. The user's password is effectively bound to the user's identification in a timely, efficient, and simple manner.<<ETX>>","PeriodicalId":329505,"journal":{"name":"[1989] Proceedings. Fifth International Conference on Data Engineering","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1989-02-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127115083","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The aggregative closure operator is defined and its usefulness is demonstrated in a wide variety of applications. The concepts and definitions of closed semirings and the aggregating relational operators provide a mathematical framework for the presentation of algorithms for these applications. A novel algorithm is also presented which is intended for the computation of the aggregate closure. All of these algorithms but the last are generalizations of existing algorithms intended for transitive closure.<>
{"title":"Aggregative closure: an extension of transitive closure","authors":"I. Cruz, T. Norvell","doi":"10.1109/ICDE.1989.47239","DOIUrl":"https://doi.org/10.1109/ICDE.1989.47239","url":null,"abstract":"The aggregative closure operator is defined and its usefulness is demonstrated in a wide variety of applications. The concepts and definitions of closed semirings and the aggregating relational operators provide a mathematical framework for the presentation of algorithms for these applications. A novel algorithm is also presented which is intended for the computation of the aggregate closure. All of these algorithms but the last are generalizations of existing algorithms intended for transitive closure.<<ETX>>","PeriodicalId":329505,"journal":{"name":"[1989] Proceedings. Fifth International Conference on Data Engineering","volume":"29 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1989-02-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122771428","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A theoretical framework for wait-for systems is provided, and general characteristics of a correct algorithm for deadlock detection and resolution are presented. It is shown that the computational upper bounds (number of messages) for deadlock detection and resolution are both O(n/sup 3/) in the worst case when n transactions are involved. This result is better than previous ones, which often are even exponential. Two correct deadlock detection and resolution algorithms are described which both achieve these upper bounds.<>
{"title":"Towards efficient algorithms for deadlock detection and resolution in distributed systems","authors":"ShouHan Wang, G. Vossen","doi":"10.1109/ICDE.1989.47228","DOIUrl":"https://doi.org/10.1109/ICDE.1989.47228","url":null,"abstract":"A theoretical framework for wait-for systems is provided, and general characteristics of a correct algorithm for deadlock detection and resolution are presented. It is shown that the computational upper bounds (number of messages) for deadlock detection and resolution are both O(n/sup 3/) in the worst case when n transactions are involved. This result is better than previous ones, which often are even exponential. Two correct deadlock detection and resolution algorithms are described which both achieve these upper bounds.<<ETX>>","PeriodicalId":329505,"journal":{"name":"[1989] Proceedings. Fifth International Conference on Data Engineering","volume":"1402 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1989-02-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114841235","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The feasibility of inferring functional dependencies from an example relation is investigated. The problem occurs in the context of automatic database design, when a tool is needed to assist the database designer in the process of specifying logical dependencies. The complexity of the dependency inference problem is inherently exponential. However, algorithms could be developed that perform well when the input relation has certain characteristics. Two such algorithms for dependency inference are implemented and optimized. An extensive set of experiments is presented, in which dependencies were inferred from example relations with different cardinalities, number of attributes, and degree of normalization. It is concluded that for practical example relations, an adequate implementation of a dependence inference function leads to acceptable interactive response times.<>
{"title":"A feasibility and performance study of dependency inference (database design)","authors":"D. Bitton, Jeffrey Millman, Solveig Torgersen","doi":"10.1109/ICDE.1989.47271","DOIUrl":"https://doi.org/10.1109/ICDE.1989.47271","url":null,"abstract":"The feasibility of inferring functional dependencies from an example relation is investigated. The problem occurs in the context of automatic database design, when a tool is needed to assist the database designer in the process of specifying logical dependencies. The complexity of the dependency inference problem is inherently exponential. However, algorithms could be developed that perform well when the input relation has certain characteristics. Two such algorithms for dependency inference are implemented and optimized. An extensive set of experiments is presented, in which dependencies were inferred from example relations with different cardinalities, number of attributes, and degree of normalization. It is concluded that for practical example relations, an adequate implementation of a dependence inference function leads to acceptable interactive response times.<<ETX>>","PeriodicalId":329505,"journal":{"name":"[1989] Proceedings. Fifth International Conference on Data Engineering","volume":"43 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1989-02-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117106041","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：