A database system that is based on the universal relation (UR) model aims at freeing its users from specifying access paths on both the physical and on the logical levels. All information about the logical structure of the database (i.e., its conceptual scheme) is hidden from users; they need only to know the attribute names, which now carry all the semantics of the database. Previous work on UR interfaces has concentrated on the design and implementation of query languages that serve to facilitate retrieval of data from a relational database. On the other hand, updates are always handled as before, which means that users still have to know the logical structure of the database in case they want to insert, delete, or modify tuples. In this paper the concepts underlying a UR interface, which is really “universal,” are presented; it is based on the UR model, and it permits not only queries but also updates: Combinations of attributes that may participate in an update-operation ("objects") have to be specified during the design phase of the database, and are then embodied into the database scheme by an extended synthesis algorithm. They form the basis for any insertion or deletion operation. A precise definition of “insertable” tuples, and of the insert- and delete-operation in this new context, is given. It is then shown that these operations modify a database state in such a way that a representative instance always exists. This is accomplished by providing a more detailed version of Sagiv's uniqueness condition and by exploring the structure of nonunique objects. Since the underlying database always has a representative instance, this instance can be used to define the window function for retrieval. It is shown that it is still possible to compute windows by a union of minimal extension joins.

Article Updating a relational database through a universal schema interface Share on Authors: Volkert Brosda View Profile , Gottfried Vossen View Profile Authors Info & Claims PODS '85: Proceedings of the fourth ACM SIGACT-SIGMOD symposium on Principles of database systemsMarch 1985 Pages 66–75https://doi.org/10.1145/325405.325414Online:25 March 1985Publication History 12citation73DownloadsMetricsTotal Citations12Total Downloads73Last 12 Months2Last 6 weeks1 Get Citation AlertsNew Citation Alert added!This alert has been successfully added and will be sent to:You will be notified whenever a record that you have chosen has been cited.To manage your alert preferences, click on the button below.Manage my AlertsNew Citation Alert!Please log in to your account Save to BinderSave to BinderCreate a New BinderNameCancelCreateExport CitationPublisher SiteGet Access

Article Free Access Share on A high-level user interface for update and retrieval in relational databases—language aspects Authors: Gottfried Vossen Technical University of Aachen, Lehrstuhl fuer Informatik III, Buechel 29 - 31, D-5100 Aachen, West Germany Technical University of Aachen, Lehrstuhl fuer Informatik III, Buechel 29 - 31, D-5100 Aachen, West GermanyView Profile , Volkert Brosda Technical University of Aachen, Lehrstuhl fuer Informatik III, Buechel 29 - 31, D-5100 Aachen, West Germany Technical University of Aachen, Lehrstuhl fuer Informatik III, Buechel 29 - 31, D-5100 Aachen, West GermanyView Profile Authors Info & Claims SIGMOD '85: Proceedings of the 1985 ACM SIGMOD international conference on Management of dataMay 1985 Pages 343–353https://doi.org/10.1145/318898.318934Published:01 May 1985Publication History 1citation262DownloadsMetricsTotal Citations1Total Downloads262Last 12 Months23Last 6 weeks6 Get Citation AlertsNew Citation Alert added!This alert has been successfully added and will be sent to:You will be notified whenever a record that you have chosen has been cited.To manage your alert preferences, click on the button below.Manage my AlertsNew Citation Alert!Please log in to your account Save to BinderSave to BinderCreate a New BinderNameCancelCreateExport CitationPublisher SiteeReaderPDF