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Efficiently publishing relational data as XML documents

Jayavel Shanmugasundaram, Eugene Shekita, Rimon Barr, Michael Carey, Bruce Lindsay, Hamid Pirahesh, Berthold Reinwald
2001 The VLDB journal  
Towards that goal, one of the major challenges is finding a way to efficiently structure and tag data from one or more tables as a hierarchical XML document.  ...  Our results also show the superiority of having the relational engine use what we call an "outer union plan" to generate the content of an XML document.  ...  Figure 3 : 3 SQL Query to Construct XML Documents from Relational Data Figure 5 : 5 Space Figure 6 :Figure 7 : 67 De-Correlated SQL Query with Aggregations Query for Redundant Relation Content Select  ... 
doi:10.1007/s007780100052 fatcat:pkok4hf5sbe7hnskpkj37rptku

X-data: Generating test data for killing SQL mutants

Bhanu Pratap Gupta, Devang Vira, S. Sudarshan
2010 2010 IEEE 26th International Conference on Data Engineering (ICDE 2010)  
Our work focuses in particular on a class of join/outer-join mutants, which are a common cause of error.  ...  Intuitively, a mutant is a query variant that could have been the correct query if the query was in error; a mutant is killed by a dataset if the original query and the mutant return different results  ...  SPACE OF MUTANTS CONSIDERED In this paper, we consider single block SQL queries with join/outer-join operations and predicates in the where clause, which correspond to select/project/join/outer-join queries  ... 
doi:10.1109/icde.2010.5447862 dblp:conf/icde/GuptaVS10 fatcat:764n33e5rvhvrfo53eom4oimp4

Parallelizing query optimization

Wook-Shin Han, Wooseong Kwak, Jinsoo Lee, Guy M. Lohman, Volker Markl
2008 Proceedings of the VLDB Endowment  
Many commercial RDBMSs employ cost-based query optimization exploiting dynamic programming (DP) to efficiently generate the optimal query execution plan.  ...  Randomized or heuristic search algorithms reduce query optimization time for large join queries by considering fewer plans, sacrificing plan optimality.  ...  This is especially true for star and clique queries, which will benefit most from parallel execution.  ... 
doi:10.14778/1453856.1453882 fatcat:5acatldmonerber723oelrkhne

Optimizing Nested Queries with Parameter Sort Orders

Ravindra Guravannavar, H. S. Ramanujam, S. Sudarshan
2005 Very Large Data Bases Conference  
Nested iteration, if implemented properly, can also win over decorrelation for several classes of queries.  ...  Nested iteration is an important technique for query evaluation. It is the default way of executing nested subqueries in SQL.  ...  with parameter bindings being generated from an outer query block.  ... 
dblp:conf/vldb/GuravannavarRS05 fatcat:3dblsbosonedfeh7tlyitnzcd4

Preparing Data Sets for the Data Mining Analysis using the Most Efficient Horizontal Aggregation Method in SQL

Jasna S, Manu J Pillai
2014 International Journal of Computer Applications  
The main aim is to identify the most efficient method from these three methods in terms of time and space complexity.  ...  A huge amount of time is needed for making the dataset for the data mining analysis because data mining practitioners required to write complex SQL queries and many tables are to be joined to get the aggregated  ...  Then left outer join is to be performed between these tables. SPJ method also requires more space than CASE and PIVOT.  ... 
doi:10.5120/15047-3415 fatcat:iq5cd2nrizgw5avyublx4irkjq

BiOpt: Bi-Level Optimization for Few-Shot Segmentation [article]

Jinlu Liu and Liang Song and Yongqiang Qin
2020 arXiv   pre-print
The learning procedure of BiOpt is decomposed into two nested loops: inner and outer loop. On each task, the inner loop aims to learn optimized prototypes from the query images.  ...  The outer loop aims to learn a discriminative embedding space across different tasks. Extensive experiments on two benchmarks verify the superiority of our proposed BiOpt algorithm.  ...  Outer optimization is further applied to learn a discriminative embedding space across different tasks.  ... 
arXiv:2011.11245v1 fatcat:wg3gzmexlzf7tgdrgxtgnyanou

4.-8. März 2019

Bernhard Radke, Thomas Neumann
2019 Datenbanksysteme für Business, Technologie und Web  
Large queries with, e. g., outer joins are quite common and having to fall back on simple greedy heuristics in this case is highly undesirable.  ...  In this work we remove both limitations: First, we generalize the underlying linearization strategy to handle non-inner joins, which allows us to linearize the search space of arbitrary queries.  ...  [Vo18] , about 20% of the join queries do contain at least one outer join with a maximum of 247 outer joins in a single query.  ... 
doi:10.18420/btw2019-05 dblp:conf/btw/Radke019 fatcat:zqa43ctfbrfxjn5vujd36fn34a

Distributed Processing of Location-Based Aggregate Queries Using MapReduce

Yuan-Ko Huang
2019 ISPRS International Journal of Geo-Information  
sum distance query (SSumDQ) are new types of location-based queries.  ...  The location-based aggregate queries, consisting of the shortest average distance query (SAvgDQ), the shortest minimal distance query (SMinDQ), the shortest maximal distance query (SMaxDQ), and the shortest  ...  In the experimental space, we also generate a set of m query points (where m varies from 0.1 K to 10 K).  ... 
doi:10.3390/ijgi8090370 fatcat:yta6fywhsbh6xlinwj24egq4le

Shortest path and distance queries on road networks

Lingkun Wu, Xiaokui Xiao, Dingxiong Deng, Gao Cong, Andy Diwen Zhu, Shuigeng Zhou
2012 Proceedings of the VLDB Endowment  
Using a variety of real road networks with up to twenty million vertices, we evaluated each technique in terms of its preprocessing time, space consumption, and query efficiency (for both shortest path  ...  and distance queries).  ...  from the interior of C to the exterior of its outer shell.  ... 
doi:10.14778/2140436.2140438 fatcat:jjmy2d2ipvfnbp476zwtf7bqc4

Shortest Path and Distance Queries on Road Networks: An Experimental Evaluation [article]

Lingkun Wu, Xiaokui Xiao, Dingxiong Deng, Gao Cong, Andy Diwen Zhu, Shuigeng Zhou
2012 arXiv   pre-print
Using a variety of real road networks with up to twenty million vertices, we evaluated each technique in terms of its preprocessing time, space consumption, and query efficiency (for both shortest path  ...  and distance queries).  ...  from the interior of C to the exterior of its outer shell.  ... 
arXiv:1201.6564v1 fatcat:hdl7wabkqvg2pjj6gasb4okyiu

A Structured Perspective of Volumes on Active Learning [article]

Xiaofeng Cao, Ivor W. Tsang, Guandong Xu
2020 arXiv   pre-print
the enclosing space of outer volume.  ...  To touch the version space from Euclidean space, we propose a theoretical bridge called Volume-based Model that increases the 'sampling target-independent'.  ...  (a) The outer volume is represented by a circumscribed hypersphere which will exclude any outlier (non-promising) hypotheses from the version space globally.  ... 
arXiv:1807.08904v2 fatcat:kz7foig3ifas3ohkcfyf3o34xy

Shared Execution Approach to ε-Distance Join Queries in Dynamic Road Networks

Hyung-Ju Cho
2018 ISPRS International Journal of Geo-Information  
The ε-distance join queries are well studied in the Euclidean space [19, 20] and in the metric space [13] [14] [15] [16] [17] [18] .  ...  Given a query point q, a threshold distance ε, and a set of objects S, a range query retrieves objects that are within the threshold distance ε from the query point q.  ...  Therefore, many studies have evaluated the efficiency of ε-distance join queries in the Euclidean space [19, 20] and in the metric space [13] [14] [15] [16] [17] [18] .  ... 
doi:10.3390/ijgi7070270 fatcat:cfbecin3fjayfhqc7yeikw4dfq

Optimization of Multi-Query based on Heuristic Approach

Prof. Isalkar A. D.
2017 IARJSET  
Multi-query optimization has often been viewed as impractical, since earlier algorithms were exhaustive, and explore a doubly exponential search space.  ...  Each operation is a part of one of the join algorithms, such as transferring a page from disk to memory, or partitioning the content of a page.  ...  The next record from the outer relation is then read and the whole of the inner relation is again scanned, and so on.  ... 
doi:10.17148/iarjset.2017.4546 fatcat:ldofypzbvrhldk4ol3oxgx6w5e

Recursive Query Facilities in Relational Databases: A Survey [chapter]

Piotr Przymus, Aleksandra Boniewicz, Marta Burzańska, Krzysztof Stencel
2010 Communications in Computer and Information Science  
The relational model is the basis for most modern databases, while SQL is the most commonly used query language.  ...  A newer standard, called the SQL-99, introduced recursive queries which can be used to solve such tasks.  ...  queries N --N -N Referencing CTE Table 2 . 2 Features Comparison-Details TEMP SPACE prevents the server from utilizing an unlimited amount of space for the TEMP file.  ... 
doi:10.1007/978-3-642-17622-7_10 fatcat:pwmtluvx55echk2zctvy5ukm24

A Self-adjusting Data Structure for Multidimensional Point Sets [chapter]

Eunhui Park, David M. Mount
2012 Lecture Notes in Computer Science  
The data structure is based on a quadtree-like subdivision of space. Like a quadtree, the data structure implicitly encodes a subdivision of space into cells of constant combinatorial complexity.  ...  Given a query point q, an access query returns the leaf node of T whose cell contains q. (Thus, it can be thought of as a point location query for the subdivision of space induced by T .)  ...  The problem is that such leaf cells may generally contain points are very far from f , relative to the query box.  ... 
doi:10.1007/978-3-642-33090-2_67 fatcat:ex3ixuoc4ba7jhvmzmndegpxz4
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