An introduction to database management systems
Problems with customized systems in the 1950s led to the development of operating systems for input/output routines. A second generation offered more generalized file management. This provided sophisticated links between data elements. Corporate database management systems appeared in the 1970s. The...
| Published in: | Program |
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| Format: | Article in Journal/Newspaper |
| Language: | English |
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Emerald
1984
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| Online Access: | http://dx.doi.org/10.1108/eb046869 https://www.emerald.com/insight/content/doi/10.1108/eb046869/full/xml https://www.emerald.com/insight/content/doi/10.1108/eb046869/full/html |
| Summary: | Problems with customized systems in the 1950s led to the development of operating systems for input/output routines. A second generation offered more generalized file management. This provided sophisticated links between data elements. Corporate database management systems appeared in the 1970s. The functions of a DBMS are given as — integration (avoiding data duplication); data independence (separating data from software); data handling; privacy; integrity controls; compatibility; concurrency support and support of complex files. Data definition is achieved through the Data Definition Language (DDL), the Data Manipulation Language (DML) and the Query and Requesting Systems (QRS). Classifying these systems can be based on the way the data is presented to the user. However, the stored data may be structured hierarchically (tree), networked (plex), relational or extended networks like MDBS III. The article ends with a review of use and selection of such software systems. 7 diagrams. No refs. |
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