Run-Time Support for Hierarchic Records in Persistent Languages
Subtyping among record types is a basic feature of typed database languages supporting the semantic or the object-oriented data-model. It is often supported by recording labels in records and implementing field access as a linear search. We study a more efficient approach, based on the idea of dividing records into an access structure and a label-free tuple, and of sharing and optimizing the access structures. For different records different access structures can be exploited, based on a linear, direct or hash organization, depending on the size and on the usage of the different records. We report experimental and analytic results on this approach.
KeywordsHash Function Hash Table Access Structure Record Type Linear Search
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- A. Albano, L. Cardelli, and R. Orsini. Galileo: A strongly typed, interactive conceptual language. ACM Transactions on Database Systems,10(2):230260, 1985.Google Scholar
- L. Cardelli. Amber. In Combinators and Functional Programming Languages, Proc. of the 13th summer school of the LITP, Le Val D’Ajol, Vosges (France),number 242 in LNCS, Berlin, 1986. Springer-Verlag.Google Scholar
- L. Cardelli. Typeful programming. Research Report 45, Digital System Research Center, Palo Alto, CA, May 1989.Google Scholar
- R. C. H. Connor, A. Dearle, R. Morrison, and A. L. Brown. An object addressing mechanism for statically typed languages with multiple inheritance. In N. Meyrowitz, editor, Proc. of Object Oriented Programming Systems Languages and Applications (OOPSLA) ‘89, New Orleans, Louisiana, number 24 (10) in Special Issue of SIGPLAN Notices, pages 279–285. ACM Press, 1989.Google Scholar
- R. Dixon and P. Schweizer. A fast method dispatcher for compiled languages with multiple inheritance. In N. Meyrowitz, editor, Proc. of Object Oriented Programming Systems Languages and Applications (OOPSLA) ‘89, New Orleans, Louisiana, number 24 (10) in Special Issue of SIGPLAN Notices, pages 211–214. ACM Press, 1989.Google Scholar