URI | http://purl.tuc.gr/dl/dias/8D1F3487-D2A0-43E8-A2D6-EDF966051916 | - |
Αναγνωριστικό | https://dl.acm.org/citation.cfm?doid=505241.505244 | - |
Αναγνωριστικό | https://doi.org/10.1145/505241.505244 | - |
Γλώσσα | en | - |
Μέγεθος | 22 pages | en |
Τίτλος | On a model of indexability and its bounds for range queries | en |
Δημιουργός | Samoladas Vasilis | en |
Δημιουργός | Σαμολαδας Βασιλης | el |
Δημιουργός | Koutsourias Elias | en |
Δημιουργός | Miranker, Daniel P | en |
Δημιουργός | Hellerstein, Joseph, 1952- | en |
Δημιουργός | Papadimitriou, Christos H | en |
Εκδότης | Association for Computing Machinery | en |
Περίληψη | We develop a theoretical framework to characterize the hardness of indexing data sets on block-access memory devices like hard disks. We define an indexing workload by a data set and a set of potential queries. For a workload we can construct an indexing scheme, which is a collection of fixed-sized subsets of the data. We identify two measures of efficiency for an indexing scheme on a workload: storage redundancy, r (how many times each item in the data set is stored), and access overhead, A (how many times more blocks than necessary does a query retrieve). For many interesting families of workloads, there exists a trade-off between storage redundancy and access overhead. Given a desired access overhead A, there is a minimum redundancy that any indexing scheme must exhibit. We prove a lower-bound theorem for deriving the minimum redundancy. By applying this theorem we show interesting upper and lower bounds and trade-offs between A and r in the case of multi-dimensional range queries and set queries. | en |
Τύπος | Peer-Reviewed Journal Publication | en |
Τύπος | Δημοσίευση σε Περιοδικό με Κριτές | el |
Άδεια Χρήσης | http://creativecommons.org/licenses/by/4.0/ | en |
Ημερομηνία | 2015-10-16 | - |
Ημερομηνία Δημοσίευσης | 2002 | - |
Θεματική Κατηγορία | Information systems | en |
Θεματική Κατηγορία | Data management systems | en |
Θεματική Κατηγορία | Data structures | en |
Θεματική Κατηγορία | Data access methods | en |
Βιβλιογραφική Αναφορά | J. Hellerstein, E. Koutsoupias, D. Miranker, C. Papadimitriou and V. Samoladas, "On a model of indexability and its Bounds for range queries," J ACM, vol. 49, no. 1, pp. 33-55, Jan. 2002. doi: 10.1145/505241.505244 | en |