Proceedings of the 1st ACM SIGACT-SIGMOD symposium on Principles of database systems最新文献

{"title":"Foundations for multifile design by application partitioning","authors":"D. Rotem, Frank Wm. Tompa, D. Kirkpatrick","doi":"10.1145/588111.588154","DOIUrl":"https://doi.org/10.1145/588111.588154","url":null,"abstract":"Two principal characteristics of database systems are the !.arcc volume of data and the diversity of application programs' requirements. Individual application programs, however, typically require a relatively small fraction of the data -often values from a subset of the records and almost certainly values from only a few of the attributes. This observation leads directly to the consideration of clustering techniques for distributed databases or, when geographical distribution is not required, for file segmentation.","PeriodicalId":126896,"journal":{"name":"Proceedings of the 1st ACM SIGACT-SIGMOD symposium on Principles of database systems","volume":"66 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1982-03-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130936139","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}

{"title":"An algorithm for minimizing roll back cost","authors":"V. Hadzilacos","doi":"10.1145/588111.588128","DOIUrl":"https://doi.org/10.1145/588111.588128","url":null,"abstract":"0. Introduction Most automatic crash recovery mechanisms for database systems are based on the concept of transaction commitment. Speaking very informally, when the system designamtes a transaction to be committed, it \"promises\" to install in the database all the updates effected by that transaction. Put another way, should a crash occur after a transaction has become committed, the transaction may not be restarted. If, however, a _ crash occurs before a transaction has become committed, that transaction must be restarted. Several mechanisms that achieve this behavior have been proposed by database system designers (e.g. [R 751, [Lo 771, [G 781, [Li 791). In all these systems, when a transaction is restarted, it is \"rolled back\" all the way to the beginning. One exception to this rule is System-R which allows to roll an uncommitted transaction back to an earlier \"savepoint\", which is not necessarily its beginning [A 761. In this paper we investigate the problem of finding the optimal set of savepoints (one per transaction) to which uncommitted transactions executing concurrently must be rolled back after a crash, so that the recovery cost is minimized. This paper is organized as follows. Section 1 informally motivates the problem. In Section 2 we present a more formal model of transaction execution in terms of which our results are stated and proved. In Section 3 we give an algorithm for the problem under consideration and prove its correctness and optimality. In many environments, cascading restarts are considered intolerable, and sufficiently restrictive schedulers are used Permission to copy without fee all or part of this material is granted provided that the copies are not made or distributed for direct commercial advantage, the ACM copyright notice and the ,title of the publication and its date appear, and notice is given that copying is by permission of the Association for Computing Machinery. To copy otherwise, or to republish, requires a fee and/or specific permission. to prevent them. In such environments the problem dealt with in this paper has a trivial solution. This issue is discussed in Section 4. 1. The Problem-We consider a database system in which transactions operate on the database concurrently. The system periodically takes \"transaction save-points\" for the transactions currently active. A transaction savepoint involves saving the current state of a transaction in non-volatile storage. What exactly constitutes the \"current state\" of a transaction depends on details that we do not care to …","PeriodicalId":126896,"journal":{"name":"Proceedings of the 1st ACM SIGACT-SIGMOD symposium on Principles of database systems","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1982-03-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123795461","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}

{"title":"Session details: Session 10","authors":"Patricia Johann","doi":"10.1145/3262687","DOIUrl":"https://doi.org/10.1145/3262687","url":null,"abstract":"","PeriodicalId":126896,"journal":{"name":"Proceedings of the 1st ACM SIGACT-SIGMOD symposium on Principles of database systems","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1982-03-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121776650","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}

{"title":"Theory of serializablity for a parallel model of transactions","authors":"R. Krishnamurthy, U. Dayal","doi":"10.1145/588111.588158","DOIUrl":"https://doi.org/10.1145/588111.588158","url":null,"abstract":"In this paper we present a parallel program schema model of a transaction system and generalize the concept of serializability from the sequential two-step model to a parallel multi-step model. We define two classes of serializable executions, and for each class we discuss two problems: recognition and scheduling. It is shown that the results for the recognition and online scheduling problems for the sequential model generalize to the parallel model. But it is argued that online scheduling is not suitable for a parallel execution environment. Therefore, batch schedulers are defined and a minimal set of precedence constraints is derived. Finally, it is shown that any optimal batch scheduler that uses syntactic information alone cannot be efficient.","PeriodicalId":126896,"journal":{"name":"Proceedings of the 1st ACM SIGACT-SIGMOD symposium on Principles of database systems","volume":"52 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1982-03-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131796618","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}

{"title":"A universal relation database system implemented via the network model","authors":"S. Kuck, Y. Sagiv","doi":"10.1145/588111.588135","DOIUrl":"https://doi.org/10.1145/588111.588135","url":null,"abstract":"We describe a network schema design algorithm that uses a well-designed relational schema as input. The resulting network database handles incomplete information, since we use only the modified foreign-key constraint and not the universal instance assumption. We believe that the representative instance is a correct representation of information stored in the database. We show how to map the representative instance to the network database. We give two algorithms for translating a relational query to a network application program. The first algorithm is confined to relational queries that express selections and projections over the universal relation scheme. The second algorithm includes all relational queries over select, project and (natural) join. Optimization techniques are discussed for both types of translation.","PeriodicalId":126896,"journal":{"name":"Proceedings of the 1st ACM SIGACT-SIGMOD symposium on Principles of database systems","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1982-03-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124696808","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}

{"title":"An operational approach to data bases","authors":"N. Spyratos","doi":"10.1145/588111.588147","DOIUrl":"https://doi.org/10.1145/588111.588147","url":null,"abstract":"We present a model-independent treatment of some important data base problems. Our approach uses the data base update as elementary concept. The basic tool is the data base view defined by a set of data base updates rather than by the usual view definition mapping.","PeriodicalId":126896,"journal":{"name":"Proceedings of the 1st ACM SIGACT-SIGMOD symposium on Principles of database systems","volume":"77 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1982-03-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124790198","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}

{"title":"Session details: Session 6","authors":"C. Yu","doi":"10.1145/3248287","DOIUrl":"https://doi.org/10.1145/3248287","url":null,"abstract":"","PeriodicalId":126896,"journal":{"name":"Proceedings of the 1st ACM SIGACT-SIGMOD symposium on Principles of database systems","volume":"69 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1982-03-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121708613","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}

{"title":"Connections in acyclic hypergraphs: extended abstract","authors":"D. Maier, J. Ullman","doi":"10.1145/588111.588118","DOIUrl":"https://doi.org/10.1145/588111.588118","url":null,"abstract":"We demonstrate a sense in which the equivalence between blocks (subgraphs without articulation points) and biconnected components (subgraphs in which there are two edge-disjoint paths between any pair of nodes) that holds in ordinary graph theory can be generalized to hypergraphs. The result has an interpretation for relational databases that the universal relations described by acyclic join dependencies are exactly those for which the connections among attributes are defined uniquely. We also exhibit a relationship between the process of Graham reduction [6] of hypergraphs and the process of tableau reduction [1] that holds only for acyclic hypergraphs.","PeriodicalId":126896,"journal":{"name":"Proceedings of the 1st ACM SIGACT-SIGMOD symposium on Principles of database systems","volume":"59 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1982-03-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121134618","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}

{"title":"The tree property is fundamental for query processing","authors":"N. Goodman, O. Shmueli","doi":"10.1145/588111.588119","DOIUrl":"https://doi.org/10.1145/588111.588119","url":null,"abstract":"One can partition the class of relational database schemas into tree schemas and cyclic schemas. In this paper we examine query processing implications of the partitioning; other areas impacted include dependency theory, schema design and graph theory.We consider a class of queries that compute the join of all relations in the database projected onto a prescribed set of attributes. We show that solving such queries (using the join, project and semijoin operators) is tantamount to creating an \"embedded\" tree schema which we call a tree projection. This lends further credibility to the pivotal nature of the tree/cyclic partitioning.Using the tree projection concept we analyze the problem of determining how many joins are needed to solve a query.","PeriodicalId":126896,"journal":{"name":"Proceedings of the 1st ACM SIGACT-SIGMOD symposium on Principles of database systems","volume":"74 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1982-03-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127376387","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}

{"title":"Independent database schemas","authors":"M. Graham, M. Yannakakis","doi":"10.1145/588111.588144","DOIUrl":"https://doi.org/10.1145/588111.588144","url":null,"abstract":"Abstract A database schema is independent with respect to a given set of constraints if the constraints can be enforced separately in the relations. A polynomial time algorithm is presented that recognizes independent schemas, when the given constraints consist of functional dependencies and the join dependency of the database schema.","PeriodicalId":126896,"journal":{"name":"Proceedings of the 1st ACM SIGACT-SIGMOD symposium on Principles of database systems","volume":"2011 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1982-03-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128203966","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}