This paper will examine two data base management systems; IMS, an example of a hierarchical data base management system and System R, a relational system. Each system will be described in general terms followed by a discussion of their relative performance. A claim is made that IMS, because of its structure and the procedural nature of its language can be more efficient than System R. Some examples are given to illustrate this claim. There is an increasing need today for readily available information; thus more and more information is being stored in disk files to facilitate rapid retrieval. A relational approach to data base management permits a high-level non-procedural interface for the user, which is important if more people require access to information in a flexible fashion and can not afford or wait for traditional application development. If however a relational data base management system is not as efficient as hierarchical or network systems then new retrieval methods must be found. Associative processors are introduced as a possible solution to this problem and three examples are discussed. RAP, a relational associative processor developed at the University of Toronto, has been used in a performance study to demonstrate the dramatic performance improvements offered by associative processors. This is also discussed. / Science, Faculty of / Computer Science, Department of / Graduate

The correctness (or integrity) of a database may be destroyed when the database is accessed concurrently by a number of independent transactions. Part of the job of a database management system is to control concurrency so that correctness is guaranteed. This thesis examines concurrency controls in general, and in particular those provided by the Educational Data Base System (EDBS). It is concluded that EDBS facilities are not sufficient to guarantee correctness. Several alternatives are proposed whereby correctness can be guaranteed. An approach is selected based on ease of implementation rather than on the degree of concurrency provided. Guaranteeing correctness and at the same time providing a high degree of concurrency turns out to be a very difficult problem both in theory and in practice. / Science, Faculty of / Computer Science, Department of / Graduate

No description available.

No description available.

No description available.

Typescript (photocopy). / Digitized by Kansas Correctional Industries

No description available.

No description available.

No description available.

No description available.