Selecting Topics for Web Resource Discovery: Efficiency Issues in a Database Approach

Al-Hamdani, Abdullah; Özsoyoǧlu, Gültekin

doi:10.1007/978-3-540-45227-0_77

Cited by 3 publications

(5 citation statements)

References 7 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The goal in our work is different, leading to different strategies. Al-Hamdani et al [1] considered topic-selection queries on top of meta-data. Their output is a list of k answers such that each answer is above a pre-defined threshold.…”

Section: Related Workmentioning

confidence: 99%

“…Each list L i consists of pairs of object id and its relevance score (oid, s i (oid)), and is sorted in a non-increasing order of s i (oid). We assume that object scores on each list are normalized such that they are in the range of [0,1], where a score of 1 implies the highest relevancy and 0 is the lowest. Given a query and some monotonic aggregation function defined over the set scores of the query attributes, we want to retrieve the top-k most relevant objects.…”

Section: A Data Model and Notationmentioning

confidence: 99%

“…We make two important observations about random access in optimal traces: (1) random accesses occur always after sorted accesses have been finished, and (2) random access are only useful to objects in R exact . To see (1), consider a trace with optimal relative precision that first makes some sorted accesses, then some random accesses, and then again some sorted accesses. The result of this schedule is identical to the result of a trace that first does all sorted accesses and then the random accesses.…”

Section: B Including Random Accessesmentioning

confidence: 99%

See 2 more Smart Citations

Best-Effort Top-k Query Processing Under Budgetary Constraints

Shmueli-Scheuer

Mass

et al. 2009

2009 IEEE 25th International Conference on Data Engineering

View full text Add to dashboard Cite

Abstract-We consider a novel problem of top-k query processing under budget constraints. We provide both a framework and a set of algorithms to address this problem. Existing algorithms for top-k processing are budget-oblivious, i.e., they do not take budget constraints into account when making scheduling decisions, but focus on the performance to compute the final topk results. Under budget constraints, these algorithms therefore often return results that are a lot worse than the results that can be achieved with a clever, budget-aware scheduling algorithm. This paper introduces novel algorithms for budget-aware top-k processing that produce results that have a significantly higher quality than those of state-of-the-art budget-oblivious solutions.

show abstract

Section: Related Workmentioning

confidence: 99%

Section: A Data Model and Notationmentioning

confidence: 99%

Section: B Including Random Accessesmentioning

confidence: 99%

See 1 more Smart Citation

Best-Effort Top-k Query Processing Under Budgetary Constraints

Shmueli-Scheuer

Mass

et al. 2009

2009 IEEE 25th International Conference on Data Engineering

View full text Add to dashboard Cite

show abstract

“…Two such works on top-k selection were Chaudhuri and Gravano [1999] and Chang and Hwang [2002], and the latter also supported expensive predicates. We have discussed the processing of SVA selection operator elsewhere [Al-Hamdani andÖzsoyoǧlu 2003]. An early algorithm for top-k join was provided in Fagin [1999], and it was further optimized by Güntzer et al [2000].…”

Section: Ranked Query Evaluationmentioning

confidence: 99%

“…In this article, we concentrate on the join evaluation algorithms; selection evaluation algorithms are discussed elsewhere [Al-Hamdani andÖzsoyoǧlu 2003] Finally, as illustrated in Example 1.1 with the prerequisite relationship, a recursive topic closure operator is useful for user queries. Such an operator serves to retrieve topics related to each other via a particular metalink type, or, more generally, via a regular expression of metalink types.…”

Section: Introductionmentioning

confidence: 99%

Querying web metadata

Özsoyoǧlu

Altıngövde

Al-Hamdani

et al. 2004

ACM Trans. Database Syst.

Self Cite

View full text Add to dashboard Cite

In this article, we discuss the issues involved in adding a native score management system to object-relational databases, to be used in querying Web metadata (that describes the semantic content of Web resources). The Web metadata model is based on topics (representing entities), relationships among topics (called metalinks), and importance scores (sideway values) of topics and metalinks. We extend database relations with scoring functions and importance scores. We add to SQL score-management clauses with well-defined semantics, and propose the sidewayvalue algebra (SVA), to evaluate the extended SQL queries. SQL extensions and the SVA algebra are illustrated through two Web resources, namely, the DBLP Bibliography and the SIGMOD Anthology.SQL extensions include clauses for propagating input tuple importance scores to output tuples during query processing, clauses that specify query stopping conditions, threshold predicates (a type of approximate similarity predicates for text comparisons), and user-defined-function-based predicates. The propagated importance scores are then used to rank and return a small number A preliminary version of this article was published in Proceedings of the VLDB 2002 Conference. This work was supported in part by a joint grant from the National Science Foundation (grant INT-9912229) of the U.S. and TUBITAK (grant 100U024) of Turkey, and the National Science Foundation grants ITR-0312200 and DBI-0218061. Authors' addresses: G.Özsoyoǧlu, A. Al-Hamdani, and Z. M.Özsoyoǧlu EECS Department, Case Western Reserve University, Cleveland, OH 44106; email: {tekin,abd,ozsoy}eecs.cwru.edu; I. S. Altingövde, andÖ. Ulusoy, Computer Engineering Department, Bilkent University, Ankara 06800, Turkey; email: {ismail,oulusoy}@cs.bilkent.edu.tr}; S. A.Özel-Özalp (current address): Industrial Engineering Department, Uludag University, Gorukle, Bursa 16059, Turkey; email: ayseozalp@ uludag.edu.tr. Permission to make digital/hard copy of part or all of this work for personal or classroom use is granted without fee provided that the copies are not made or distributed for profit or commercial advantage, the copyright notice, the title of the publication, and its date appear, and notice is given that copying is by permission of ACM, Inc. To copy otherwise, to republish, to post on servers, or to redistribute to lists requires prior specific permission and/or a fee. of output tuples. The query stopping conditions are propagated to SVA operators during query processing. We show that our SQL extensions are well-defined, meaning that, given a database and a query Q, under any query processing scheme, the output tuples of Q and their importance scores stay the same.To process the SQL extensions, we discuss two sideway value algebra operators, namely, sideway value algebra join and topic closure, give their implementation algorithms, and report their experimental evaluations.

show abstract