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Technical University of Crete
Technical University of Crete
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EL
| URI | http://purl.tuc.gr/dl/dias/FA5231DA-D168-4CB2-AA1A-FDAF32CF9E93 | - |
| Identifier | https://doi.org/10.1016/0306-4379(84)90017-6 | - |
| Language | en | - |
| Title | Estimating block selectivities | en |
| Creator | Christodoulakis Stavros | en |
| Creator | Χριστοδουλακης Σταυρος | el |
| Publisher | Elsevier | en |
| Content Summary | In many data base performance studies there is a need to estimate the number of records of a file which qualify in a query, as well as the number of blocks of secondary storage which contain these records. In this paper we present a model of data base contents and data placement on devices. We extend a multivariate statistical model that was used for the estimation of record selectivities in [5] to model the distribution of records that qualify in a query among the blocks of secondary storage. Then we show how to obtain estimates of block selectivities and we compare our estimates with the estimates of previous models. | en |
| Type of Item | Peer-Reviewed Journal Publication | en |
| Type of Item | Δημοσίευση σε Περιοδικό με Κριτές | el |
| License | http://creativecommons.org/licenses/by/4.0/ | en |
| Date of Item | 2015-11-25 | - |
| Date of Publication | 1984 | - |
| Subject | Information Systems | en |
| Bibliographic Citation | S. Christodoulakis, "Estimating block selectivities", Information Systems, vol. 9, no. 1, pp. 69-79, 1984. doi: 10.1016/0306-4379(84)90017-6 | en |
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