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The Multi-Lingual and Multi-Model Database System (MDBS), at the Naval Postgraduate School, is the only database system in which five different database model interfaces operate on a single computer system. The purpose of the MDBS is to prove that multiple database models can coexist and share data within a single computer system. The MDBS provides a platform in which diverse database models can share data, via access to other models' base data, stored in the MDBS common format. The problem was that a Functional database model had not previously been implemented on the MDBS. The goal of this thesis was to provide a Functional/DAPLEX interface for the MDBS. The approach was to design and implement a set of programs to encapsulate the Functional/DAPLEX language as introduced by D.W Shipman in 1981. It is imperative that the interface maintain the look, feel and characteristics of the Functional data model. The result is a set of programs, written in C, which implement a Functional/DAPLEX interface, thus a sixth interface, for the MDBS. The programs parse DAPLEX data definition language and data manipulation language constructs, convert them to an MDBS common format, store the data with other models' base data and can reconvert MDBS common data back to a Functional form. |
