Decompiling CODASYL DML into relational queries

• Main Authors: R. H. Katz, E. Wong
• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Published: 1982
• Subjects: General Terms; Algorithms Additional Key Words and Phrases; decompilation; semantic data models; 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

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