An External Schema Facility for CODASYL 1978.

Eric K. Clemons: An External Schema Facility for CODASYL 1978. VLDB 1979: 119-128
  author    = {Eric K. Clemons},
  editor    = {Antonio L. Furtado and
               Howard L. Morgan},
  title     = {An External Schema Facility for CODASYL 1978},
  booktitle = {Fifth International Conference on Very Large Data Bases, October
               3-5, 1979, Rio de Janeiro, Brazil, Proceedings},
  publisher = {IEEE Computer Society},
  year      = {1979},
  pages     = {119-128},
  ee        = {db/conf/vldb/Clemons79.html},
  crossref  = {DBLP:conf/vldb/79},
  bibsource = {DBLP,}


We propose as an extension to the CODASYL Data Description Language a new external schema facility more powerful than that presently offered by CODASYL subschemas. We note that the present facility relies on records and sets that closely resemble those employed in the schema, with unfortunate implications for programmer productivity, data independence, and communications channel traffic. We propose instead a powerful external schema facility that, in effect, offers applications programmers a virtual data base. This data base, while derivable from the stored data base, is not constrained to resemble it in form; thus programmers will use records formatted, not like those stored in the common data base, but like the cognitive structures employed in program development. A possible language for external schema definition is introduced.

Copyright © 1979 by The Institute of Electrical and Electronic Engineers, Inc. (IEEE). Abstract used with permission.

ACM SIGMOD Anthology

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Printed Edition

Antonio L. Furtado, Howard L. Morgan (Eds.): Fifth International Conference on Very Large Data Bases, October 3-5, 1979, Rio de Janeiro, Brazil, Proceedings. IEEE Computer Society 1979
Contents BibTeX


Umeshwar Dayal, Philip A. Bernstein: On the Updatability of Relational Views. VLDB 1978: 368-377 BibTeX
Eric K. Clemons: An External Schema Facility to Support Data Base Update. JCDKB 1978: 371- BibTeX
Eric K. Clemons: The External Schema and CODASYL. VLDB 1978: 130 BibTeX
Eric K. Clemons: Rational data base standards: an examination of the 1978 CODASYL DDLC Report. Inf. Syst. 4(1): 235-239(1979) BibTeX
CODASYL: Reports of the Data Description Language Committee. Inf. Syst. 3(4): 247-320(1978) BibTeX
Robert W. Engles: An Analysis of the April 1971 Data Base Task Group Report. SIGFIDET Workshop 1971: 69-91 BibTeX
Frederick H. Lochovsky, Dennis Tsichritzis: User Performance Considerations in DBMS Selection. SIGMOD Conference 1977: 128-134 BibTeX
Frank Manola: On Relating the CODASYL Database Languages and the ANSI/SPARC Framework. VLDB 1978: 132 BibTeX
Frank Manola: A Review of the 1978 CODASYL Database Specifications. VLDB 1978: 232-242 BibTeX
Diane C. P. Smith: Conversion and the CODASYL Framework. VLDB 1978: 133-134 BibTeX
Robert W. Taylor: Data Administration and the DBTG Report. SIGMOD Workshop, Vol. 1 1974: 431-444 BibTeX
Dennis Tsichritzis, Anthony C. Klug: The ANSI/X3/SPARC DBMS Framework Report of the Study Group on Dabatase Management Systems. Inf. Syst. 3(3): 173-191(1978) BibTeX

Referenced by

  1. Peter Ursprung, Carl August Zehnder: HIQUEL: An Interactive Query Language to Define and Use Hierarchies. ER 1983: 299-314
  2. Eric K. Clemons: Design of an External Schema Facility to Define and Process Recursive Structures. ACM Trans. Database Syst. 6(2): 295-311(1981)
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