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Filtering with Approximate Predicates

Narayanan Shivakumar, Hector Garcia-Molina, Chandra Chekuri
1998 Very Large Data Bases Conference  
Approximate predicates can be used to reduce the number of comparisons made by expensive, complex predicates.  ...  We also study the complexity of our optimization strategies under various scenarios, and we present an experimental case study that illustrates the potential gains achieved by optimizing queries with approximate  ...  With approximate predicates, the optimizer has to consider a much larger space of plans, since each user query can now be replaced with one of several alternate queries with approximate predicates.  ... 
dblp:conf/vldb/ShivakumarGC98 fatcat:uv2sff5dcbadtm2mmw47rn2ivy

Fuzzy Logic-Based Event Notification in Sparse MANETs

Anna Lekova, Katrine Skjelsvik, Thomas Plagemann, Vera Goebel
2007 21st International Conference on Advanced Information Networking and Applications Workshops (AINAW'07)  
It is built on two new ideas: using features as multi-attribute indexes of the subscription and predicate patterns for processing subscriptions with arbitrary Boolean operators.  ...  In most event notification solutions, subscriptions are formed with crisp values or crisp value ranges.  ...  We have implemented and evaluated the performance of a filtering algorithm with nonindexing of predicates in subscriptions, with and without sorted features and covered subscriptions.  ... 
doi:10.1109/ainaw.2007.194 dblp:conf/aina/LekovaSPG07 fatcat:3nywgrpc6bdy3lalb3x3j5eaku

Conditional Cuckoo Filters [article]

Daniel Ting, Rick Cole
2020 arXiv   pre-print
Bloom filters, cuckoo filters, and other approximate set membership sketches have a wide range of applications. Oftentimes, expensive operations can be skipped if an item is not in a data set.  ...  We propose the Conditional Cuckoo Filter, a simple modification of the cuckoo filter that allows for set membership testing given predicates on a pre-computed sketch.  ...  Prebuilt Bloom or other approximate set membership filters can further restrict the set of ids to approximately those in the intersection of ci, t, and mc but without predicates applied.  ... 
arXiv:2005.02537v1 fatcat:aqyzy6smfncv7bdvgsf7t5hcae

LOOK: A Lazy Object-Oriented Kernel design for geometric computation

Stefan Funke, Kurt Mehlhorn
2002 Computational geometry  
It combines different kinds of floating-point filter techniques and a lazy evaluation scheme with the exact number types provided by LEDA allowing for efficient and exact computation with rational and  ...  It is the first kernel design which uses floating-point filter techniques on the level of geometric constructions.  ...  is d; if d = 1, evaluate the predicate exactly, (2) evaluate all objects with depth d exactly and improve their floating-point approximations, (3) reevaluate the floating-point approximations of all objects  ... 
doi:10.1016/s0925-7721(01)00046-3 fatcat:lwzenzumzzgkpj5bujlza2rt2y

Look --- a Lazy Object-Oriented Kernel for geometric computation

Stefan Funke, Kurt Mehlhorn
2000 Proceedings of the sixteenth annual symposium on Computational geometry - SCG '00  
It combines different kinds of floating-point filter techniques and a lazy evaluation scheme with the exact number types provided by LEDA allowing for efficient and exact computation with rational and  ...  It is the first kernel design which uses floating-point filter techniques on the level of geometric constructions.  ...  is G ; if G H PI , evaluate the predicate exactly 2. evaluate all objects with depth G exactly and improve their floating-point approximations 3. reevaluate the floating-point approximations of all objects  ... 
doi:10.1145/336154.336196 dblp:conf/compgeom/FunkeM00 fatcat:agmnhm2qjnfzfedcsxjonqo7vu

Optimizing Inequality Joins in Datalog with Approximated Constraint Propagation [chapter]

Dario Campagna, Beata Sarna-Starosta, Tom Schrijvers
2012 Lecture Notes in Computer Science  
Our approach approximates the well-known propagation technique from Constraint Programming.  ...  Table 4 shows the results of evaluating the CMR variant of the Flights program without (CMR) and with (CMR+FP) filter predicate transformation for a collection of 19 different data graphs, with different  ...  For every rule with one or more arithmetic constraints, it identifies the generator predicate atoms, exploits the constraints to produce corresponding filter predicates, and replaces the generator atoms  ... 
doi:10.1007/978-3-642-27694-1_9 fatcat:q6nnuuhrd5h4hlelg2bovtikje


2001 International journal of computational geometry and applications  
Applying a new semi-static filter, EXPCOMP combines the speed of static filters with the power of dynamic filters.  ...  The filter stages deal with all kinds of floating-point exceptions, including underflow. The resulting programs show a very good runtime behaviour.  ...  We have measured five different implementations: orig original impl. using LEDA real r lazy-eval, no filter stages dr lazy-eval, with fp-filter dir lazy-eval, with 3-level filter d lazy eval, only fp filter  ... 
doi:10.1142/s0218195901000493 fatcat:ipbgxww5vndcplcwno5qcjwbye

Indirect Predicates for Geometric Constructions

Marco Attene
2020 Computer-Aided Design  
This makes it possible to keep track of the floating point approximation, and thus to exploit efficient filters and expansion arithmetic to exactly resolve the predicate with minimal overhead with respect  ...  Modern implementations employ floating point filtering techniques to combine efficiency and robustness, and state-of-the-art predicates are guaranteed to be always exact while being only slightly slower  ...  Such an approximation may lead to invalid configurations (e.g. with self intersections) even if the combinatorics is exact.  ... 
doi:10.1016/j.cad.2020.102856 fatcat:7ec3re3hi5bgfeyk6kmmuuqusi

Approximating Constraint Propagation in Datalog [article]

Dario Campagna, Beata Sarna-Starosta, Tom Schrijvers
2011 arXiv   pre-print
We present a technique exploiting Datalog with aggregates to improve the performance of programs with arithmetic (in)equalities.  ...  Our approach employs a source-to-source program transformation which approximates the propagation technique from Constraint Programming.  ...  Similar filter predicates are generated for the remaining generator atoms.  ... 
arXiv:1112.3787v1 fatcat:gesnfzqtandgbpdag2iisr7foy


Hua-Gang Li, S. Alireza Aghili, Divyakant Agrawal, Amr El Abbadi
2006 Proceedings of the 15th international conference on World Wide Web - WWW '06  
An XML range query may impose predicates on the numerical or textual contents of the elements and/or their respective path structures.  ...  In this paper, we propose a dynamic summarization and indexing method, FLUX, based on Bloom filters and B + -trees to tackle these problems.  ...  We call this class of queries Fuzzy-Range (FuR) since they provide efficient support for exact and approximate (fuzzy) matching of queries with path, content and range predicates.  ... 
doi:10.1145/1135777.1136025 dblp:conf/www/LiAAA06 fatcat:6alubwtu6veoji2tl33lwbkthu

Interval arithmetic yields efficient dynamic filters for computational geometry

Hervé Brönnimann, Christoph Burnikel, Sylvain Pion
1998 Proceedings of the fourteenth annual symposium on Computational geometry - SCG '98  
We validate our approach experimentally, comparing it with other static, dynamic and semi-static filters.  ...  We show that interval techniques can be used to speed up the exact evaluation of geometric predicates and describe an efficient implementation of interval arithmetic that is strongly influenced by the  ...  The predicates in the algorithm compare two y intersect, or an input abscissa with a x maximum, or two x maximum values.  ... 
doi:10.1145/276884.276903 dblp:conf/compgeom/BronnimannBP98 fatcat:q3vqqfrygnborhhz7opaju3dse

Trajectory queries and octagons in moving object databases

Hongjun Zhu, Jianwen Su, Oscar H. Ibarra
2002 Proceedings of the eleventh international conference on Information and knowledge management - CIKM '02  
We propose to divide trajectory predicates into topological and non-topological parts; extend the 9-intersection model of Egenhofer-Franzosa to a 3-step evaluation strategy for trajectory queries: a filter  ...  The filter and refinement steps are similar to region searches. As in spatial databases, approximations of trajectories are typically used in evaluating trajectory queries.  ...  We develop a 3-step strategy for evaluating a trajectory predicate as follows. 1. Filtering: perform a region search on approximations of trajectory segments. 2.  ... 
doi:10.1145/584792.584860 dblp:conf/cikm/ZhuSI02 fatcat:ubqckc74gjb7pl6cyudau5lgzi

Software Pipelining for Packet Filters [chapter]

Yoshiyuki Yamashita, Masato Tsuru
2007 Lecture Notes in Computer Science  
Using predicated execution and enhanced modulo scheduling, we solve this problem and achieve 20 times higher performance compared with a conventional interpreter-based packet filter.  ...  We also compare the proposed filters and compiler-based packet filters, and obtain a better than two-fold increase in performance.  ...  We solve this program with predicated execution [4] and enhanced modulo scheduling [9] .  ... 
doi:10.1007/978-3-540-75444-2_44 fatcat:bltaumv535ejzih5js733opyde

Boolean query mapping across heterogeneous information sources

K. Chen-Chuan Chang, H. Garcia-Molina, A. Paepcke
1996 IEEE Transactions on Knowledge and Data Engineering  
The results are then processed by a filter query to yield the correct final result.  ...  However, there are also a wealth of search engines behind these libraries, each with a different document model and query language.  ...  In this case, our approach will be to approximate the predicate "distributed (W) system" by the closest predicate supported by Folio, "distributed AND system."  ... 
doi:10.1109/69.536244 fatcat:k6avraigjnd2hm246m2jmxdmom


Matko Botinčan, Domagoj Babić
2013 Proceedings of the 40th annual ACM SIGPLAN-SIGACT symposium on Principles of programming languages - POPL '13  
By combining dynamic symbolic execution to discover symbolic input-output steps of the programs and counterexample guided abstraction refinement to over-approximate program behavior, Sigma * transforms  ...  We define a class of stream filters-programs that process streams of data items-for which Sigma * converges to a complete model if abstraction refinement eventually builds up a sufficiently strong abstraction  ...  Using the approximate post operator on Pred(Φ) computed with predicate abstraction we obtain the transition relation on abstract states.  ... 
doi:10.1145/2429069.2429123 dblp:conf/popl/BotincanB13 fatcat:zbozefsolbd3nkybvs6fbeulme
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