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Skyline queries, front and back

Jan Chomicki, Paolo Ciaccia, Niccolo' Meneghetti
2013 SIGMOD record  
Skyline queries are a popular way to obtain preferred answers from the database by providing only the orderings of attribute values.  ...  The result of a skyline query consists of those input tuples for which there is no input tuple having better or equal values in all the attributes and a better value in at least one attribute.  ...  The identity r 1 \ r 2 \ sky A (r 1 [ r 2 ) = sky A (r 1 ) \ sky A (r 2 ) is then used to compute the result, the intuition being that if t 2 C, then t 2 sky A (r) i↵ it is in the local skylines sky A  ... 
doi:10.1145/2536669.2536671 fatcat:js2mz2b3ozd6rfsfsb7scwsdji

Z-SKY: an efficient skyline query processing framework based on Z-order

Ken C. K. Lee, Wang-Chien Lee, Baihua Zheng, Huajing Li, Yuan Tian
2009 The VLDB journal  
While derived upon coherent ideas and concepts, our approaches are shown to outperform the state-of-the-art algorithms that are specialized to address particular skyline problems, especially when a large  ...  Given a set of data points in a multidimensional space, a skyline query retrieves those data points that are not dominated by any other point in the same dataset.  ...  Also, dominance tests in SFS and SaLSa are based on an exhaustive scan on existing skyline candidates. Unless the number of skyline points is very small, they tend to be CPU-bound.  ... 
doi:10.1007/s00778-009-0166-x fatcat:wsto6whotzby3ayv64mej6woni

Efficient computation of combinatorial skyline queries

Yu-Chi Chung, I-Fang Su, Chiang Lee
2013 Information Systems  
The past skyline query is a special case of the combinatorial skyline query.  ...  In this paper, we generalize the concept of skyline query and introduce a novel type of query, the combinatorial skyline query, which is to find the outstanding combinations from all combinations of the  ...  be pruned without being computed), the computation cost of IDA under the correlated dataset can be greatly reduced.  ... 
doi:10.1016/j.is.2012.10.005 fatcat:bvfo7tuylzdq7bqfqaacdlnrdq

Evaluating skylines in the presence of equijoins

Wen Jin, Michael D. Morse, Jignesh M. Patel, Martin Ester, Zengjian Hu
2010 2010 IEEE 26th International Conference on Data Engineering (ICDE 2010)  
method for estimating the skyline selectivity of the joined table ; (3) evaluation of skyline computation based on the estimation method and the proposed evaluation techniques; and (4) a systematic experimental  ...  When a database system is extended with the skyline operator, it is important to determine the most efficient way to execute a skyline query across tables with join operations.  ...  This research was supported in part by the National Science Foundation under grant IIS-0929988.  ... 
doi:10.1109/icde.2010.5447841 dblp:conf/icde/JinMPEH10 fatcat:j3vx7hjhsfdl7ldhcek2zy2tqq

Output-sensitive Evaluation of Prioritized Skyline Queries

Niccolo' Meneghetti, Denis Mindolin, Paolo Ciaccia, Jan Chomicki
2015 Proceedings of the 2015 ACM SIGMOD International Conference on Management of Data - SIGMOD '15  
Prioritized skylines (p-skylines) take into account non-compensatory preferences, where some dimensions are deemed more important than others, and trade-offs are constrained by the relative importance  ...  Additionally, we develop a general framework for benchmarking p-skyline algorithms, showing how to sample prioritized preference relations uniformly, and how to highlight the effect of data correlation  ...  P-SKYLINES IN EXTERNAL MEMORY In the past scan-based skyline algorithms like Bnl, Sfs, SaLSa or Less have generated a considerable interest in the database community.  ... 
doi:10.1145/2723372.2723736 dblp:conf/sigmod/MeneghettiMCC15 fatcat:ilwnfgxqcve3vebshbzezv5eoq

A Survey of Skyline Query Processing [article]

Christos Kalyvas, Theodoros Tzouramanis
2017 arXiv   pre-print
This paper surveys the state-of-the-art techniques for skyline query processing, the numerous variations of the initial algorithm that were proposed to solve similar problems and the application-specific  ...  Based on this the skyline query was proposed which is a decision support mechanism, that retrieves the valuefor- money options of a dataset by identifying the objects that present the optimal combination  ...  An intermediate set S of skyline points. Output: Return an updated set S. skyline query and its family of related queries along with the state-of-the-art related algorithms.  ... 
arXiv:1704.01788v1 fatcat:g45oxbmrznhqtmcpabud3sap7e

BSkyTree

Jongwuk Lee, Seung-won Hwang
2010 Proceedings of the 13th International Conference on Extending Database Technology - EDBT '10  
computation.  ...  Our experimental results demonstrate that proposed algorithms outperform state-of-the-art skyline algorithms up to two orders of magnitude.  ...  This paper thus aims to find the cost-optimal strategy for a systematic pivot point selection, considering both dominance and incomparability in "non-index" skyline computation without pre-computed structures  ... 
doi:10.1145/1739041.1739067 dblp:conf/edbt/LeeH10 fatcat:mri5yhphm5f6nnmaanqqcjpxza

Skyline computation for frequent queries in update intensive environment

R.D. Kulkarni, B.F. Momin
2016 Journal of King Saud University: Computer and Information Sciences  
For such frequent, overlapping skyline queries repeating computations on large datasets result in unacceptable response time.  ...  the metadata of the skyline queries.  ...  This field gets its values when the whole dataset is scanned for computing the skyline for the first novel query and it is referred for computing the new skyline whenever the dataset undergoes any of the  ... 
doi:10.1016/j.jksuci.2015.04.003 fatcat:px4by7tlfjachc4fiplelge7tm

Textually Relevant Spatial Skylines

Jieming Shi, Dingming Wu, Nikos Mamoulis
2016 IEEE Transactions on Knowledge and Data Engineering  
STD computes a skyline which not only satisfies the intent of STS, but also has a small and easy-to-interpret size.  ...  We propose an efficient algorithm for computing STD-based skylines, which operates on an IR-tree that indexes the data.  ...  Algorithm SS scans the sorted list and checks whether each object is in the skyline by comparing it with the previously found skyline objects.  ... 
doi:10.1109/tkde.2015.2465374 fatcat:ukx3s5qfeje3lanxrbxzt6vdve

Advanced Indexing and Query Processing for Multidimensional Databases

Evangelos Dellis, Seeger, Bernhard (Prof. Dr.), Datenbanksysteme
2011
Therefore, the general goal of this thesis is the improvement of the efficiency of index based query processing in high-dimensional data spaces and the development of novel query operators.  ...  The basic idea is to split the data space vertically into multiple low- and medium-dimensional data spaces.  ...  Index Another index-based progressive technique called Index method, which can output the skyline without having to scan the whole dataset, is introduced in [116] and [44] .  ... 
doi:10.17192/z2007.0676 fatcat:j666c7iplfckrldebinxaa4s5y

My life as a night elf priest: an anthropological account of World of Warcraft

2010 ChoiceReviews  
Taking up in-depth portraits of different aspects of living and growing up in a media-saturated era, the series takes an innovative approach to the genre of the ethnographic monograph.  ...  Her many publications include The Internet  ...  For common journeys on mounts that delivered players to their destinations without the need for player control, I could, for many travel paths, unload a whole dishwasher full of dishes, gather up and put  ... 
doi:10.5860/choice.48-2170 fatcat:p23svqewtfbtrknc65p4br4c6i

Tightrope

Alaric Lejano
2014
"I can't imagine what you can do with a hi-def video camera without the computer." "People have their reasons." We both looked at the conference room. The office was empty.  ...  The remote was missing too so whoever stole it knew what they were doing." "Hmmm," OMW said. "At least they didn't take the computer," I said. "Without it, the camera is pretty useless."  ... 
doi:10.7282/t3v986bz fatcat:roso3wzbwze6pmjhbb4anwzhqm

The Re-Conception of Cate THE RE-CONCEPTION OF CATE

Cortney Palmacci, Cortney Palmacci, Marlisa Santos, Director
2008 unpublished
He turns the mug around to inspect his work before setting it down in front of me. He's painted a city skyline with a clear blue sky.  ...  After scanning the closets and wardrobe, I realize I can't find anything that looks comfortable.  ... 
fatcat:okw5jqcmynf4de6htkb74w23c4

A Collection of Borrowed Exaggerations [article]

Douglas Neilson, University Of Calgary, University Of Calgary, Aritha Van Herk
2015
As the characters in my thesis prove, not everyone responds to the spaces around them with the best of intentions.  ...  By following characters who navigate a city they do not entirely understand, this thesis examines the roles that space and place play in the evolution of identity.  ...  He stands and stares at the sky. Wipes sweat from his brow, finds focus on the crow. What do you think? Hicks says. The crow lowers its head. Hicks scans along the cliff faces around him.  ... 
doi:10.11575/prism/24662 fatcat:25y2djmqvnejvarvt6aknzxtnu

A web-based genre analysis: investigating listings on Airbnb

Laura Gandinelli
2017 unpublished
The focus of this project is therefore to analyse computer-based texts from the tourism area, conducting a genre analysis following the ESP approach.  ...  On the basis of these results, the present project has given its contribution to the growth of computer mediated communication (CMC) area.  ...  We also encourage guests to utilize our two outdoor spaces -an elevated front porch with a fabulous sky swing which offers beautiful sunsets and skyline views and our cozy backyard patio with plenty of  ... 
doi:10.25365/thesis.47986 fatcat:xfmzx3n5dfe6nbpdeaqkqkiduy
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