Decompiling CODASYL DML into relational queries

A “decompilation ” algorithm is developed to transform a program written with the procedural operations of CODASYL DML into one which interacts with a relational system via a nonprocedural query specification. An Access Path Model is introduced to interpret the semantic accesses performed by the pro...

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Bibliographic Details
Main Authors: R. H. Katz, E. Wong
Other Authors: The Pennsylvania State University CiteSeerX Archives
Format: Text
Language:English
Published: 1982
Subjects:
DML
Online Access:http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.86.3853
http://www.eecs.berkeley.edu/~wong/wong_pubs/wong75.pdf
Description
Summary:A “decompilation ” algorithm is developed to transform a program written with the procedural operations of CODASYL DML into one which interacts with a relational system via a nonprocedural query specification. An Access Path Model is introduced to interpret the semantic accesses performed by the program. Data flow analysis is used to determine how FIND operations implement semantic accesses. A sequence of these is mapped into a relational query and embedded into the original program. The class of programs for which the algorithm succeeds is characterized. Categories and Subject Descriptors: H.2.3 [Database Management]: Languages--data manipuh-tion languages (DML); query languages; CODACYL; H.2.5 [Database Management]: Heteroge-neous Databases-program translation