MOD

Data base management systems which permit on-line manipulation and modification of records, present a unique class of problems whose solution require facilities that can guarantee reliability, consistency and flexibility. This paper presents the design ...

The separation of all representations of structural properties from data is proposed as a stratagem for data base management system (DBMS) design. The DBMS operates by creating for each user an interpreted user-oriented data base machine which utilizes ...

An authorization model is presented, applicable to a shared data base with well defined data structures. Access to this data base is made through a high level language, which is extended to permit data manipulation and to provide data views for ...

The time and cost of implementing data processing applications can be greatly reduced through the use of software systems which provide language for the expression of file-level operations on data, i.e., operations whose operands are sets of records or ...

The design of a distributed data base for a hierarchical computer system is investigated. If the transmission cost and storage cost can be calculated from linear cost functions, a data base can be decomposed based upon a simple figure of merit. Moreover,...

Little has appeared on the problems of efficiently storing, accessing, and manipulating relations. These are of considerable interest, both to implementors and those seeking comparison with other database models. In this paper we examine how one ...

An approach for implementing a "smart" interface to support a relational view of data is proposed. The basic idea is to employ automatic programming techniques so that the interface analyzes and efficiently refines the high level query specification ...

Because the user interface in a relatonal data base management system may be decoupled from the storage representation of data, novel, powerful and efficient integrity control schemes are possible. This paper indicates the mechanism being implemented in ...

In a relational data base, if a relation is listed explicitly in the data base, then questions asking whether the relation exists can be retrieved readily. There are questions that may be posed to such a system in which, although the answer is not ...

A number of file structures (e.g., inverted files and multilist files) can be modelled as a collection of records whose contents are described using sets. With each of these sets is associated a definition which is stated as a Boolean expression of ...

The design of generalized data translators, particularly in the area of data base translation, has been the subject of much research in recent years. The practical application of this research has been limited and conducted primarily at the university ...

This paper describes in detail a translation definition language, CONVERT, for specifying the mapping of the instances of source items, which may be components of one or more files, into instances of target data, which may constitute multiple files.The ...

In this paper we describe an ongoing project which is addressing the problem of converting and transferring data bases among disparate data management systems (DMSs). The difficulties in converting a data base from one DMS to another stem from the fact ...

Experience with data translation over the last two years has resulted in a definite set of requirements for the normalized representation of data when used as an intermediate form during the process. The logical requirements pertain to the ability to ...

The rapid growth of large, heterogeneous, resource-sharing computer networks has created a serious problem in the sharing of information between incompatible systems. These incompatibilities can be categorized as either physical or logical in nature. ...

This paper is a report on the current (1975 May) status of the Study Group on Data Base Management Systems in the United States. While the official purpose of this Study Group is an investigation of standardization potential in the area of data base ...

This paper addresses a problem which arises during the design of an integrated data base: this is to generate a set of physical data structures capable of supporting a desired set of logical data structures. A prototype design aid which generates ...

The functional approach to data base design is introduced. In this approach the goal of design is to derive a data structure which is capable of supporting a set of anticipated queries rather than a structure which "models the business" in some other ...

Quantitative descriptions of data populations have played an important role in the data base design process, particularly where simulation has been employed. The new levels of fidelity and representation-independence made possible by recent advances in ...

A major problem to be considered in the design of a data base is that of index selection. In this paper we present a model of a data base together with a probabilistic model for the transactions conducted with the data base: queries and updates. We ...

Data Description Languages (DDLs) usually are discussed in terms of business data processing applications. This paper describes the importance of DDLs in computer-aided design (CAD). Users of CAD systems are compared with users of business data ...

The candidate keys, as defined by E. F. Codd [4], are important in the process of reducing a normalized relation into second and third normal forms.Given a set of functional relations, Delobel and Casey [6] transformed this set into a Boolean function ...

The relational model for data base organization introduced clearly defined basic algebraic concepts whose properties are well understood. As a consequence, questions of a semantic nature arise. Due to the mathematical nature of the relational model, ...

In this paper procedures are studied for storing, accessing, updating, and reorganizing data in large files whose organization is direct, an organization used when a fast response time is required. "Distribution-dependent" hashing functions and the ...

In Codd's relational model, the relation name groups together a family of functional dependencies over a set of attributes. For integrity and for maintenance purposes it is important to eliminate inherent redundancy within a relation due to the ...