Validation algorithms for pointer values in DBTG databases
D. A. Thomas, Bernard Pagurek, Raymond J. A. Buhr · ACM Transactions on Database Systems · 1977
This paper develops algorithms for verifying pointer values in DBTG (Data Base Task Group) type databases. To validate pointer implemented access paths and set structures, two algorithms are developed. The first procedure exploits the “typed pointer” concept employed in modern programming languages to diagnose abnormalities in directories and set instances. The second algorithm completes pointer validation by examining set instances to ensure that each DBTG set has a unique owner. Sequential processing is used by both algorithms, allowing a straightforward implementation which is efficient in both time and space. As presented, the algorithms are independent of implementation schema and physical structure.