Showing papers on "Conceptual schema published in 1978"
TL;DR: The main purpose of as discussed by the authors is to establish a bridgehead between contemporary ethology and some recent work in the philosophy of mind, arguing that the distinction between behaviour categorized by function and by form is in some ways analogous to the distinction that distinguishes between behavior categorized by form and function.
53 citations
31 May 1978
TL;DR: This paper proposes a scheme for view representation which will facilitate the process of view integration by enhancing the data abstraction framework proposed by Smith and Smith and incorporated as rules and assertions about schema- and instance-level insertion and deletion.
Abstract: The process of logical database design consists of four phases: view modeling, view integration, schema optimization and schema mapping View modeling is defined as the modeling of the usage and information structure perspectives of the real world from the point of view of different users and/or applications The view integration phase combines these views into a single community view which is subjected to further optimization and mapping As a result, instances of users' model may be altered and application programs transformedThis paper proposes a scheme for view representation which will facilitate the process of view integration This is done by enhancing the data abstraction framework proposed by Smith and Smith It takes into account the instance-level interrelationships among data and the identification of instances via these interrelationships The usage perspective is incorporated as rules and assertions about schema- and instance-level insertion and deletionThe problem of view integration is briefly addressed Valid transformations of views are indicated as a part of the integration process
52 citations
01 May 1978
TL;DR: Criteria and methodologies for the conceptual design of databases, particularly in large and sophisticated applications, are addressed and a methodology for designing an abstract syntax specification is outlined.
Abstract: Criteria and methodologies for the conceptual design of databases, particularly in large and sophisticated applications, are addressed. For a design to be understandable to user and designer alike, intuitive methods for abstracting concepts from a mass of detail must be employed. Two abstraction methods are particularly important — aggregation and generalization. Aggregation forms a concept by abstracting a relationship between other concepts (called components). Generalization forms a concept by abstracting a class of other concepts (called categories). The principle of "object relativity" is essential for the successful integration of abstractions. This principle states that individuals, categories, relationships and components are just different ways of viewing the same abstract objects. Using this principle a design may be hierarchically organized into independently meaningful abstractions. An "abstract syntax" is introduced to specify these abstraction hierarchies. An advantage of this abstract syntax is that some concepts do not have to be arbitrarily classified as "roles". The principle of "individual preservation" is a minimal requirement for maintaining the semantics of aggregation and generalization. It states that every user-invokeable operation must preserve the integrity of individuals. A methodology for designing an abstract syntax specification is outlined. The simplicity of this methodology is directly due to the principles of object relativity and individual preservation.
32 citations
Proceedings Article•
13 Sep 1978
TL;DR: A global model for the design of a complete IS including data programs and time dynamics is defined and the IS conceptual schema consistent with this orientation is presented and it is presented that ensures the non-redudancy quality of the IS data and processings.
Abstract: The current Information System (IS) design methods restrict the IS design to the one based upon data bases. They totally omit to consider processing aspects. Nevertheless complete representation of real phenomena needs the simultaneous design and realisation of the IS three components : data, processing and their operational dynamics. We take in account all of these aspects and try to develop a piloting system for the design and realisation of IS (REMORA project). In this paper we define a global model for the design of a complete IS including data programs and time dynamics and we present the IS conceptual schema consistent with this orientation. This model is one of relational type. Its definition begins by a representation of the perceived reality analysed in terms of three categories : objects, operations, events. The integrity constrainsts associated to the model concepts allow the definition of the normalized conceptual schema that in particular ensures the non-redudancy quality of the IS data and processings.
27 citations
TL;DR: In this paper a binary model for the Conceptual Schema is illustrated through the specification of a set of primitives, and the elements of a language for the definition of a binary Schema and of the corresponding operations are given.
15 citations
Proceedings Article•
13 Sep 1978
TL;DR: This paper presents both a data model and a method for its practical use for the construction of the logical data base structure according to the concepts of the given model.
Abstract: This paper presents both a data model and a method for its practical use. There are two main parts : the first one deals with the data model, new concepts adequate for the design of conceptual schema are introduced. The second part presents complete method for the construction of the logical data base structure according to the concepts of the given model.
9 citations
01 Jan 1978
5 citations
10 Oct 1978
TL;DR: This paper deals with the description of the information system dynamics at the conceptual level and proposes a classification of "event" relations — the tuples of which are the starting point of treatments — and of "permanent" relations.
Abstract: This paper deals with the description of the information system dynamics at the conceptual level. A model is put forward to take into account both the structural and dynamic aspects of data base. The data model (an entity-relation model) helps to build the data into a structured set of relations that correspond to a specific third normal form. These relations do not play the same role in data base evolution : we propose a classification of "event" relations — the tuples of which are the starting point of treatments — and of "permanent" relations. The description of processings deriving from a primary event may be divided into elementary chronological steps with the help of a hierarchy graph. Each step can be analyzed in term of "states" which express the stage of treatment of the triggering event.
5 citations
31 May 1978
TL;DR: The data base management scene has been characterized since 1968 by a series of debates in which intractable positions have been taken on issues which to observers have seemed diffuse.
Abstract: The data base management scene has been characterized since 1968 by a series of debates in which intractable positions have been taken on issues which to observers have seemed diffuse. The first public debate was in August 1968 at a panel session at the ACM National Conference in Las Vegas. The transcript of this session was published in the SIGBDP quarterly Data Base in Fall 1969 under the title "The Large Data Base its Organization and User Interface". The issue under consideration at the time was "self-contained" versus "host language" and can be seen to have resolved itself with the passage of time with the recognition that (as Charlie Bachman said at the time) "both are needed." Since then we have had DBTG versus Guide-Share in 1971-72 and what has become a hardy perennial "relational versus network."
3 citations
TL;DR: A data structure matrix is used to identify and interrelate entry types of the data base and the derived schema is a feasible DBTG-schema, i.e. the information requirements are retained in the entry and set types defined.
3 citations
31 May 1978
TL;DR: The basic functions of an aggregate schema facility are discussed, as well as their implementation in a CODASYL/DBTG-like environment and potential applications to dynamic translation and distributed databases.
Abstract: Supporting multiple user views of databases is currently an important problem area in database management system development An interesting facet of this problem arises whenever a user needs an integrated view of several distinct databases Using traditional database concepts, an aggregate schema facility has been developed to address this problem The basic functions of an aggregate schema facility are discussed, as well as their implementation in a CODASYL/DBTG-like environment Interest in an aggregate schema facility grew out of a problem in restructuring large databases The application of this facility to restructuring is discussed, as well as potential applications to dynamic translation and distributed databases
13 Nov 1978
TL;DR: A data base design methodology which utilizes multiple levels of design abstraction is outlined and an example of the design of conceptual, logical and physical data base structures utilizing this methodology is presented.
Abstract: A data base design methodology which utilizes multiple levels of design abstraction is outlined. An example of the design of conceptual, logical and physical data base structures utilizing this methodology is presented. The importance of a good conceptual schema model is emphasized and a two-step conceptual schema design process is proposed. The design of logical and physical schemas is illustrated for a CODASYL model environment, taking into consideration the 1978 CODASYL DDL and DSDL specifications.
TL;DR: Ten information policy issues within these two caregories are covered and an attempt to clarify management tasks is made.
01 Jan 1978
TL;DR: For Sellars, what is true is what is correctly assertible within a conceptual structure under the semantic rules that describe that structure, and Teirceish would be the language sanctioned by the semantical rules of an ideal conceptual scheme.
Abstract: For Sellars, what is true is what is correctly assertible within a conceptual structure under the semantic rules that describe that structure. But conceptual structures are not static; they evolve. And they do so, Sellars claims, in a well-determined fashion that makes each successor conceptual structure in a sense more adequate than its predecessor. So it is reasonable on that view to “conceive of a language which enables its users to form ideally adequate pictures of objects. . ,”1 It would be the language sanctioned by the semantical rules of an ideal conceptual scheme. Sellars calls the language Teirceish.’ What is ultimately true, then, is what is correctly assertible according to the semantical rules of the Peirceish conceptual structure. More exactly, truth for Peirce, and for Sellars, is a limit concept. The ideal conceptual structure is provided by the ideal scientific theory. But the ideal scientific theory is something that is in principle unattainable. It is the end product of an in principle endless process of theory refinement.
13 Nov 1978
TL;DR: A relational or table oriented form for hierarchies is defined and algorithms for translating hierarchical requests into accesses against that form and back again to hierarchical form are discussed.
Abstract: A relational or table oriented form for hierarchies is defined and algorithms for translating hierarchical requests into accesses against that form and back again to hierarchical form are discussed. The symmetries inherent to a relational representation can then be used to support various transforms of the hierarchy from the same stored data. This scheme can be implemented on any system capable of supporting tables and is intended to provide data independent access for hierarchies based on a table oriented conceptual schema support system.