An introduction to database systems: vol. I (4th ed.)
An introduction to database systems: vol. I (4th ed.)
Link implementation techniques
ACM-SE 16 Proceedings of the 16th annual Southeast regional conference
Computer Database Organization, 2nd Ed
Computer Database Organization, 2nd Ed
Towards the design and implementation of a unified data base management system.
Towards the design and implementation of a unified data base management system.
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A DBMS user view consists of a Data Definition Language (DDL) which defines the data model and a Data Manipulation Language (DML) which defines the access scheme for that data model. To permit different user views to share a common data base, it is necessary to establish a single physical representation for the data base. The physical representation must be compatible with the data model of each logical view involved. This can be accomplished by mapping the DDL commands of each logical view into a set of Model Definition Primitive (MDP) commands which describe the physical representation of that logical view. The MDP descriptions of each physical representation can then be merged into one MDP description. The existence of Model Definition primitives has already been established (Dl); therefore, the purpose of this paper is twofold:1. Describe a DDL compiler for each view whose MDP output can be easily merged.2. Define the rules under which a merging program operates.In this paper we do not discuss the effects of the above merging concept on implementation of any DML.