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The Case for Deep Query Optimisation [article]

Jens Dittrich, Joris Nix
2019 arXiv   pre-print
We benchmark that operator both independently as well as in the context of DQO-enabled dynamic programming. We conclude by sketching a DQO research agenda.  ...  Query Optimisation (QO) is the most important optimisation problem in databases. The goal of QO is to compute the best physical plan under a given cost model.  ...  In the experiments in Section 5, we show how we modified dynamic programming to factor in the following meta-relational plan property: dense vs sparse and how that makes a difference in optimisation and  ... 
arXiv:1908.08341v2 fatcat:2q2j4xu6nncpfnuhfqsk4nh3cq

Dynamic Tables: An Architecture for Managing Evolving, Heterogeneous Biomedical Data in Relational Database Management Systems

J. Corwin, A. Silberschatz, P. L. Miller, L. Marenco
2007 JAMIA Journal of the American Medical Informatics Association  
to overcome limitations posed when using conventional relational database technology.  ...  The authors propose a solution to these obstacles based on a relational database engine using a sparse, column-store architecture.  ...  Our first approach was to use a dense column-store. In this architecture, a relation's attribute values are densely packed into one-column tables.  ... 
doi:10.1197/jamia.m2189 pmid:17068350 pmcid:PMC2215074 fatcat:fl7cvnugl5fgjovmyjdtfup4yy

Time-varying social networks in a graph database

Ciro Cattuto, Marco Quaggiotto, André Panisson, Alex Averbuch
2013 First International Workshop on Graph Data Management Experiences and Systems - GRADES '13  
Here we introduce a data model for time-varying social network data that can be represented as a property graph in the Neo4j graph database.  ...  In order to support the needs of specific applications, as well as general tasks related to data curation, cleaning, linking, post-processing, and data analysis, data models and data stores are needed  ...  are associated with the NEXT_LEVEL relations 3 The selected multilevel index can co-exist with other indexing structures, its use does not prevent us from using different, additional indexes in future  ... 
doi:10.1145/2484425.2484442 dblp:conf/sigmod/CattutoQPA13 fatcat:bbkaxpdpbzavrje3tkh3lslara

Intelligent Indexing—Boosting Performance in Database Applications by Recognizing Index Patterns

Alberto Arteta Albert, Nuria Gómez Blas, Luis Fernando de Mingo López
2020 Electronics  
This old-fashioned way of indexing database objects is proven to affect the database performance to some degree, creating downtime and a possible impact in the performance that is usually solved by manually  ...  The statistical analyzers embedded in the Database Management System are neither always accurate enough to automatically determine when to use an index nor to change its inner structure.  ...  This research has no funding sponsors so they had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript, or in the decision to publish  ... 
doi:10.3390/electronics9091348 fatcat:cu4qpvmcanfqjhbw7egws4aqaq

An Efficient and Scalable RDF Indexing Strategy based on B-Hashed-Bitmap Algorithm using CUDA

Sharmi Sankar, Munesh Singh, Awny Sayed, Jihad Alkhalaf Bani-Younis
2014 International Journal of Computer Applications  
Indexing enormous databases such as RDF has been a focus of intense research. As is well understood, indexing plays a pivotal role in speeding up data retrieval operations and query performance.  ...  So far, RDF data has been mostly implemented either as a RDBMS or as a non-native datastore, in both cases the sequential indexing strategy fails miserably with the scaling of the data-store.  ...  STORING AND INDEXING UNDER RELATIONAL PERSPECTIVE The RDF data in relational databases are stored as triples of a RDF graph on a single table over a relational schema (Subject, Predicate, and Object).  ... 
doi:10.5120/18216-9221 fatcat:qtjlxp7dgje3nfdfk5vie47iqu

AS-Index: A Structure for String Search Using n-Grams and Algebraic Signatures

Camelia Constantin, Cédric du Mouza, Witold Litwin, Philippe Rigaux, Thomas Schwarz
2016 Journal of Computer Science and Technology  
We present the AS-Index, a new index structure for exact string search in disk resident databases.  ...  This makes our structure a choice of interest for the class of applications that require very fast lookups in large textual databases.  ...  Non-dense index characteristics for alpha (26) filesTable 19. Non-dense index characteristics for adn filesTable 20.  ... 
doi:10.1007/s11390-016-1618-6 fatcat:4nc66amurja5xowphvl4icn2zi

Emotion-Based Classification and Indexing for Wallpaper and Textile

Yuan-Yuan Su, Hung-Min Sun
2017 Applied Sciences  
Section 2 reviews previous studies in related areas.  ...  The challenges of using dynamic color combinations for the proposed mapping method of color-emotion include dynamically determining the number of colors in the image, identifying the main color of the  ...  Section 2 reviews previous studies in related areas.  ... 
doi:10.3390/app7070691 fatcat:xc3cffdkfjfevg3b73imucg53y

Vegetation dynamics of Algerian's steppe ecosystem. Case of the region of Tiaret

Mykola M Kharytonov, Bouacha Mohamed Islem, M'hamed Maatoug
2018 Aplinkos tyrimai, inzinerija ir vadyba / Environmental Research, Engineering and Management  
Data from salinity index SI and moisture index NDWI as well as climatic data were acquired from the Google earth engine platform.  ...  Their geographical location gives them a buffer zone between the north with a sub-humid climate and the great arid Sahara in the south.  ...  of the dynamics. 2 In this sense, the data collected via Google earth engine, including salinity indices, soil moisture index and 3 climate data, were compared with vegetation classes.  ... 
doi:10.5755/j01.erem.74.1.20095 fatcat:kgk64s6fcjcwjjm26ea5oytkla

The adaptive radix tree: ARTful indexing for main-memory databases

V. Leis, Alfons Kemper, T. Neumann
2013 2013 IEEE 29th International Conference on Data Engineering (ICDE)  
Main memory capacities have grown up to a point where most databases fit into RAM. For main-memory database systems, index structure performance is a critical bottleneck.  ...  To overcome these shortcomings, we present ART, an adaptive radix tree (trie) for efficient indexing in main memory.  ...  RELATED WORK In disk-based database systems, the B + -tree [8] is ubiquitous [9] . It retrieves large blocks from disk to reduce the number of accesses.  ... 
doi:10.1109/icde.2013.6544812 dblp:conf/icde/LeisK013 fatcat:sma67ydio5c5vpuok4axiruanu

Dot-Product Join

Chengjie Qin, Florin Rusu
2017 Proceedings of the 29th International Conference on Scientific and Statistical Database Management - SSDBM '17  
The paramount challenge in designing the dot-product join operator is how to optimally schedule access to the dense relation based on the non-contiguous entries in the sparse arrays.  ...  In this paper, we propose an in-database solution for Big Model analytics.  ...  ., ⃗ u 1 < ⃗ u 2 , for U in Figure 2 since it has a non-zero entry at index 1, while the first non-zero entry in ⃗ u 2 is at index 3.  ... 
doi:10.1145/3085504.3085512 dblp:conf/ssdbm/QinR17 fatcat:7lhi75hgyvaala3eocmungxwj4

A Clustering Model for Mining Evolving Web User Patterns in Data Stream Environment [chapter]

Edmond H. Wu, Michael K. Ng, Andy M. Yip, Tony F. Chan
2004 Lecture Notes in Computer Science  
., association rules or clusters) from related static or historical databases, which greatly limits their wide adoption in online environments.  ...  Nowadays, many current and emerging Web applications require realtime monitoring and analyzing user patterns in the Web.  ...  We propose a data model for mining dynamic dense regions and dense clusters in data stream environment.  ... 
doi:10.1007/978-3-540-28651-6_83 fatcat:zgqpwjn7uzgrbk5dspsvj4ojdi

Query Optimization by Indexing in the ODRA OODBMS

Tomasz Kowalski, Michał Chromiak, Kamil Kuliberda, Jacek Wiślicki, Radosław Adamus, Kazimierz Subieta
2009 Annales UMCS Informatica  
The general idea of indices in the object-oriented databases does not differ from indexing in relational databases [1] .  ...  Many indexing methods can be adopted from relational database systems and even their applicability can be significantly extended.  ...  Nevertheless, there is a wide range of different index structures that could be used in indexing in object-oriented databases similarly to those in the solutions occurring in relational ones [11, 1, 14  ... 
doi:10.2478/v10065-009-0006-z fatcat:wqllcu77fjgzvhyx4zcy7tzmpe

Dynamic index selection in data warehouses

Stephane Azefack, Kamel Aouiche, Jerome Darmont
2007 2007 Innovations in Information Technologies (IIT)  
In this paper, we present an automatic, dynamic index selection method for data warehouses that is based on incremental frequent itemset mining from a given query workload.  ...  Preliminary experimental results illustrate the efficiency of this approach, both in terms of performance enhancement and overhead.  ...  Related work Index selection in data warehouses The index selection problem has been studied for many years in databases, but adaptations to data warehouses are few.  ... 
doi:10.1109/iit.2007.4430394 fatcat:rhepubhyrjg75mkpwr65muhvxq


Cédric du Mouza, Witold Litwin, Philippe Rigaux, Thomas Schwarz
2009 Proceeding of the 18th ACM conference on Information and knowledge management - CIKM '09  
It typically indexes every n-gram in the database, though non-dense indexing is possible. The hash function uses the algebraic signatures of n-grams.  ...  AS-Index is a new index structure for exact string search in disk resident databases. It uses hashing, unlike known alternatives, whether baesd on trees or tries.  ...  Depending on whether we use non-dense indexing or not, we could index a database of 200 GB to 1TB with expected search times in the order of a 0.1 msec to a few milli-seconds.  ... 
doi:10.1145/1645953.1645993 dblp:conf/cikm/MouzaLRS09 fatcat:bficsylhvrbbjlctnnwwuripxm

DESSIN: Mining Dense Subgraph Patterns in a Single Graph [chapter]

Shirong Li, Shijie Zhang, Jiong Yang
2010 Lecture Notes in Computer Science  
In this paper, we study the particular problem of finding frequently occurring dense subgraph patterns in a large connected graph.  ...  These properties enable us to employ an index-based method to locate all occurrences of a pattern in a graph and a depth-first search method to find all patterns.  ...  Related Work Regarding the problem studied in this paper, one category of related work is mining frequent subgraph patterns in a set of database graphs [4, 10-15, 18, 19] .  ... 
doi:10.1007/978-3-642-13818-8_15 fatcat:ocwei44cjjhvxc3engmbxqhg24
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