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Efficient Algorithms for Mining Outliers from Large Data Sets

by Sridhar Ramaswamy, Rajeev Rastogi, Kyuseok Shim , 2000
"... In this paper, we propose a novel formulation for distance-based outliers that is based on the distance of a point from its k th nearest neighbor. We rank each point on the basis of its distance to its k th nearest neighbor and declare the top n points in this ranking to be outliers. In addition ..."
Abstract - Cited by 322 (0 self) - Add to MetaCart
. In addition to developing relatively straightforward solutions to finding such outliers based on the classical nestedloop join and index join algorithms, we develop a highly efficient partition-based algorithm for mining outliers. This algorithm first partitions the input data set into disjoint subsets

Cache-Oblivious Nested-Loop Joins

by unknown authors
"... We propose to adapt the newly emerged cache-oblivious model to relational query processing. Our goal is to automatically achieve an overall performance comparable to that of fine-tuned algorithms on a multi-level memory hierarchy. This automaticity is because cache-oblivious algorithms assume no kno ..."
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no knowledge about any specific parameter values, such as the capacity and block size of each level of the hierarchy. As a first step, we propose recursive partitioning to implement cache-oblivious nested-loop joins (NLJ) without indexes, and recursive clustering and buffering to implement cache-oblivious NLJs

From Nested-Loop to Join Queries in OODB

by Hennie J. Steenhagen, Peter M. G. Apers, Henk M. Blanken, Rolf A. de By - IN PROCEEDINGS OF THE 20TH INT'L CONFERENCE ON VERY LARGE DATABASES (VLDB , 1994
"... Most declarative SQL-like query languages for object-oriented database systems (OOSQL) are orthogonal languages allowing for arbitrary nesting of expressions in the select-, from-, and where-clause. Expressions in the from-clause may be base tables as well as setvalued attributes. In this paper, we ..."
Abstract - Cited by 20 (0 self) - Add to MetaCart
are transformed into join queries as far as possible. Three optimization options are described, and a strategy to assign priorities to options is proposed.

Double Index Nested-Loop Reactive Join for Result Rate Optimization

by Mihaela A. Bornea, Vasilis Vassalos, Yannis Kotidis, Antonios Deligiannakis - Proc. IEEE Int’l Conf. Data Eng. (ICDE , 2009
"... Abstract — Adaptive join algorithms have recently attracted a lot of attention in emerging applications where data is provided by autonomous data sources through heterogeneous network environments. Their main advantage over traditional join tech-niques is that they can start producing join results a ..."
Abstract - Cited by 2 (1 self) - Add to MetaCart
as soon as the first input tuples are available, thus improving pipelining by smoothing join result production and by masking source or network delays. In this paper we propose Double Index NEsted-loops Reactive join (DINER), a new adaptive join algorithm for result rate maximization. DINER combines two

Evaluating Window Joins over Unbounded Streams

by Jaewoo Kang , Jeffrey F. Naughton, Stratis D. Viglas - IN ICDE , 2003
"... We investigate algorithms for evaluating sliding window joins over pairs of unbounded streams. We introduce a unittime -basis cost model to analyze the expected performance of these algorithms. Using this cost model, we propose strategies for maximizing the efficiency of processing joins in thre ..."
Abstract - Cited by 161 (3 self) - Add to MetaCart
in three scenarios. First, we consider the case where one stream is much faster than the other. We show that asymmetric combinations of join algorithms, (e.g., hash join on one input, nested-loops join on the other) can outperform symmetric join algorithm implementations. Second, we investigate

Relational joins on graphics processors

by Bingsheng He, Ke Yang, Rui Fang, Mian Lu, Naga Govindaraju, Qiong Luo, Pedro Sander , 2007
"... We present our novel design and implementation of relational join algorithms for new-generation graphics processing units (GPUs). The new features of such GPUs include support for writes to random memory locations, efficient inter-processor communication through fast shared memory, and a programming ..."
Abstract - Cited by 74 (12 self) - Add to MetaCart
programming model for general-purpose computing. Taking advantage of these new features, we design a set of data-parallel primitives such as scan, scatter and split, and use these primitives to implement indexed or non-indexed nested-loop, sort-merge and hash joins. Our algorithms utilize the high parallelism

Scatter Search and Path Relinking

by Fred Glover , 1999
"... The evolutionary approach called scatter search, and its generalized form called path relinking, originated from strategies for creating composite decision rules and surrogate constraints. Recent studies demonstrate the practical advantages of these approaches for solving a diverse array of optimiza ..."
Abstract - Cited by 169 (33 self) - Add to MetaCart
of optimization problems from both classical and real world settings. Scatter search and path relinking contrast with other evolutionary procedures, such as genetic algorithms, by providing unifying principles for joining solutions based on generalized path constructions (in both Euclidean and neighborhood spaces

Evaluation of Main Memory Join Algorithms for Joins with Subset Join Predicates

by Sven Helmer, Guido Moerkotte - In Proc. of the Conf. on Very Large Data Bases (VLDB , 1997
"... Current data models like the NF 2 model and object-oriented models support set-valued attributes. Hence, it becomes possible to have join predicates based on set comparison. This paper introduces and evaluates two main memory algorithms to evaluate efficiently this kind of join. More specifically, ..."
Abstract - Cited by 42 (4 self) - Add to MetaCart
, we concentrate on subset predicates. 1 Introduction Since the invention of relational database systems, tremendous effort has been undertaken in order to develop efficient join algorithms. Starting from a simple nested-loop join algorithm, the first improvement was the introduction of the merge

Fuzzy Functional Dependencies and Lossless Join Decomposition of Fuzzy Relational Database Systems

by K. V. S. V. N. Raju, Arun K. Majumdar - ACM TRANSACTIONS ON DATABASE SYSTEMS , 1988
"... This paper deals with the application of fuzzy logic in a relational database environment with the objective of capturing more meaning of the data. It is shown that with suitable interpretations for the fuzzy membership functions, a fuzzy relational data model can be used to represent ambiguities in ..."
Abstract - Cited by 96 (0 self) - Add to MetaCart
, the definition of classical functional dependency has been generalized to fuzzy functional dependency (ffd). The implication problem of ffds has been examined and a set of sound and complete inference axioms has been proposed. Next, the problem of lossless join decomposition of fuzzy relations for a given set

Fundamentals of scatter search and path relinking

by Fred Glover , Manuel Laguna , Rafael Martí - CONTROL AND CYBERNETICS , 2000
"... The evolutionary approach called Scatter Search, and its generalized form called Path Relinking, have proved unusually effective for solving a diverse array of optimization problems from both classical and real world settings. Scatter Search and Path Relinking differ from other evolutionary procedur ..."
Abstract - Cited by 139 (14 self) - Add to MetaCart
The evolutionary approach called Scatter Search, and its generalized form called Path Relinking, have proved unusually effective for solving a diverse array of optimization problems from both classical and real world settings. Scatter Search and Path Relinking differ from other evolutionary
Results 1 - 10 of 654