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With the proliferation of [[information technology]] starting in the 1970s, the job of [[information management]] had taken a new light, and also began to include the field of [[data maintenance]]. No longer was information management a simple job that could be performed by almost anyone. An understanding of the technology involved, and the theory behind it became necessary. As [[information storage]] shifted to electronic means, this became more and more difficult.
[[Image:4-2 ANSI-SPARC three level architecture.svg|thumb|320px|The notion of a three-schema model was first introduced in 1975 by the [[ANSI-SPARC Architecture|ANSI/X3/SPARC three level architecture]], which determined three levels to model data.<ref name="MW99"> Matthew West and Julian Fowler (1999). [http://www.matthew-west.org.uk/publications/princ03.pdf High Quality Data Models]. The European Process Industries STEP Technical Liaison Executive (EPISTLE).</ref>]]
In this emerging field the NIST had held a series of four workshops on Database and Information Management Directions since the 1970s. Each of the workshops addresses a specific theme:<ref>Fong and Goldfine (1989, p. 5)</ref> ▼
One of the first overall approaches to building [[information systems]] and systems [[information management]] from the 1970s was the [[three-schema approach]]. It proposes to use three different [[view model|views]] in systems development, in which [[conceptual model]]ling is considered to be the key to achieving [[data integration]]:<ref name="STRAP08"> [http://www.fas.org/irp/doddir/army/strap/strpsec2.htm STRAP SECTION 2 APPROACH]. Retrieved 30 September 2008.</ref>
* External schema for user views
* [[Conceptual schema]] integrates external schemata
* Internal schema that defines physical storage structures
At the center, the conceptual schema defines the [[Ontology_(information_science)|ontology]] of the [[concept]]s as the [[user (computing)|user]]s think of them and talk about them. The physical schema according to Sowa (2004) "describes the internal formats of the [[data]] stored in the [[database]], and the external schema defines the view of the data presented to the [[application program]]s".<ref name ="JFS04"> [[John F. Sowa]] (2004). [ "The Challenge of Knowledge Soup"]. published in: ''Research Trends in Science, Technology and Mathematics Education''. Edited by J. Ramadas & S. Chunawala, Homi Bhabha Centre, Mumbai, 2006.</ref>
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* "What information about [[database]] technology does the manager need to make prudent decisions about using new technology", in 1975.
* "What information can help a manager assess the impact on a database system?" in 1977.
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* Problems addressed by architecture
* Benefits and risks of having architecture
To illustrate the levels of architecture, what has become known as the NIST Enterprise Architecture Model, was presented (see image). In this concept the three layers of the [[three-schema approach]] are divided into five layers.
=== Application in the 1990s ===
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