| Category | Value | ||
| Available via | http://dbpubs.stanford.edu/pub/2007-7 | ||
| Submitted on | 1st of June 2007 | ||
| Author | Murthy, Raghotham; Widom, Jennifer | ||
| Title | Making Aggregation Work in Uncertain and Probabilistic Databases | ||
| Date of publication | June 2007 | ||
| Citation | Murthy, Raghotham; Widom, Jennifer. Making Aggregation Work in Uncertain and Probabilistic Databases, | ||
| Number of pages | 13 | ||
| Language | English | ||
| Project | Database Group | ||
| Type | Technical Report | ||
| Subject group | Computer Science | ||
| Abstract | We describe how aggregation is handled in the Trio system for uncertain and probabilistic data. Because ýexactý aggregation in uncertain databases can produce exponentially-sized results, we provide three alternatives: a low bound on the aggregate value, a high bound on the value, and the expected value. These variants return a single result instead of a set of possible results, and they are generally very efficient to compute for both full-table and grouped aggregation queries. We provide formal definitions and semantics, a description of our implementation, and some preliminary analytical and experimental results for the one aggregate (expected-average) for which we compute an approximation. | ||
| Keywords | Trio, Aggregations, TriQL, Probabilistic Databases, Uncertain Databases | ||
| Contact address | rsm@cs.stanford.edu | ||
| Sponsored by |
This work was supported by the National Science Foundation under grants IIS-0324431 and IIS-0414762, and by grants from the Boeing and Hewlett-Packard Corporations. | ||
| Fulltext source |
| Management of the document by | siroker@db.stanford.edu
| |