Issue No. 03 - March (1990 vol. 23)
DOI Bookmark: http://doi.ieeecomputersociety.org/10.1109/2.50270
<p>A user can formulate database queries and updates graphically, by manipulating schema diagrams. The authors based the graphical data manipulation interface on the entity-relationship (ER) model because of its widespread use and increasing popularity. They use an extended ER model incorporating various forms of generalization and specialization, including subset, union and partition relationships. They call their model the extended conceptual entity-relationship or ECER model. A comparison with other graphical entity-relationship interfaces is included.</p>
D. W. Embley, R. Elmasri, M. Rusinkiewicz and B. Czejdo, "A Graphical Data Manipulation Language for an Extended Entity-Relationship Model," in Computer, vol. 23, no. , pp. 26-36, 1990.