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A Student Information System in Restricted Domains

Purushottam Das, Mohd Mursleen, Ankur Singh Bist
2013 International Journal of Computer Applications  
User query profiling, inference rules and framing are used to infer the answer.  ...  Our approach is tried to achieve high accuracy in Student Information System (SIS) in restricted domain. The restriction leads to the question domains and extract answers.  ...  The generated answer is synthesized with the SIS system [7]. CONCLUSION This paper describes the SIS for restricted domains.  ... 
doi:10.5120/11926-7701 fatcat:h4tetwuqfvgrdklxyf6zbfte2e

Personalized DBMS: an Elephant in Disguise or a Chameleon?

Georgia Koutrika
2011 IEEE Data Engineering Bulletin  
However, the Boolean database query model has limitations. A user may run into empty answers when the query conditions are too restrictive or sift through too many results that match the query.  ...  In this paper, we explain the need towards personalized and preference-aware query answering in the context of databases and we discuss how it can be enabled.  ...  For example, integrating preferences as additional constraints to restrict a query with too many answers may lead to an empty answer.  ... 
dblp:journals/debu/Koutrika11 fatcat:pmvgagvpyfhcniyueoq6wway5i

Datalog+/-: A Family of Languages for Ontology Querying [chapter]

Andrea Calì, Georg Gottlob, Thomas Lukasiewicz, Andreas Pieris
2011 Lecture Notes in Computer Science  
In the following, we will consider the ontological query answering problem as that of answering Boolean conjunctive queries (BCQs) against a database instance D (a set of ground facts) under an ontology  ...  ., [1]) has been used as a paradigmatic database programming and query language for over three decades.  ...  In the following, we will consider the ontological query answering problem as that of answering Boolean conjunctive queries (BCQs) against a database instance D (a set of ground facts) under an ontology  ... 
doi:10.1007/978-3-642-24206-9_20 fatcat:2yqubxfcybcmbisixbcmgpgaka

Schema mappings and data exchange for graph databases

Pablo Barceló, Jorge Pérez, Juan Reutter
2013 Proceedings of the 16th International Conference on Database Theory - ICDT '13  
We then identify relevant classes of mappings and queries for which the problems of materializing solutions and query answering can be solved efficiently.  ...  We show that both problems are difficult with respect to combined complexity, and that for the latter problem, even data complexity is high for some very simple mappings and queries.  ...  We start by showing that we need to further restrict the class of NRE-restricted mappings in order to obtain efficient query answering in combined complexity for queries defined by NREs.  ... 
doi:10.1145/2448496.2448520 dblp:conf/icdt/Barcelo0R13 fatcat:6jjexu676fcm5ag5wsqbdhap7y

Query classes [chapter]

Martin Staudt, Matthias Jarke, Manfred A. Jeusfeld, Hans W. Nissen
1993 Lecture Notes in Computer Science  
The interpretation is based on a deductive database view of queries. Generic query classes are introduced with a simple parameter substitution construct.  ...  This paper proposes a language to formulate queries as classes related to the schema classes and constrained by an associative membership condition. Answers are then regarded as their instances.  ...  queries with stored answers.  ... 
doi:10.1007/3-540-57530-8_18 fatcat:jq63ztqn5va7verouef7jxh4e4

Data Expiration and Aggregate Queries

David Toman
2009 Alberto Mendelzon Workshop on Foundations of Data Management  
We investigate the space requirements for summaries needed for maintaining exact answers to aggregate queries over histories of relational databases.  ...  We show that, in general, a super-logarithmic lower bound (in the length of the history) on space needed to maintain a summary of the history in order to be able to maintain answers to counting queries  ...  Aggregate Queries We use the standard syntax for range-restricted first-order queries extended with a sum aggregate to query database histories.  ... 
dblp:conf/amw/Toman09 fatcat:ynvfegxopfbkbfftzviu3z6l6m

Towards intelligent databases [chapter]

François Bry
1993 Lecture Notes in Computer Science  
We would like to conclude this section on deductive database query answering methods with some remarks.  ...  (X «-Y). query(Yl) <-query((Yl, Y2)). query(Y2) f-query((Yl, Y2), answer(Yl). answer(X) <-query(X), fact(X). answer((Yl, Y2)) <-query((Yl, Y2)), answer(Yl), answer(Yl).  ... 
doi:10.1007/3-540-56804-2_12 fatcat:q7ioi4u725fklbxlg4tqiorioa

Restricted Predicates for Hypothetical Datalog

Fernando Sáenz-Pérez
2015 Electronic Proceedings in Theoretical Computer Science  
In this work, we cover this subject by introducing a new concept: a restricted predicate, which allows negative assumptions by pruning the usual semantics of a predicate.  ...  Introductory Example With respect to logic programming, in the context of deductive databases, the term relation is used interchangeably with predicate, rule with clause and the term query with goal.  ...  Such a hypothetical query represents that, assuming that the current database is augmented with the regular rules in R ={rulei | 1 ≤ i ≤ N}, and that the meaning of the restricting rules in R are removed  ... 
doi:10.4204/eptcs.200.5 fatcat:ylgwqaal6rfmfadlhwwymt2bs4

QPIAD: Query Processing over Incomplete Autonomous Databases

Hemal Khatri, Jianchun Fan, Yi Chen, Subbarao Kambhampati
2007 2007 IEEE 23rd International Conference on Data Engineering  
However, the autonomous nature of the databases poses several challenges, such as the restricted access privileges, limited query patterns, and sensitivity of database and network resource consumption  ...  Traditional query processing techniques that focus on the strict soundness of answer tuples often ignore tuples with critical missing attributes, even if they wind up being relevant to a user query.  ...  Retrieving highly relevant uncertain answers from such databases is challenging due to the restricted access privileges of mediator, limited query patterns supported by autonomous databases, and sensitivity  ... 
doi:10.1109/icde.2007.369028 dblp:conf/icde/KhatriFCK07 fatcat:gvjaqkfhrbe6ppaou7ugh4mnrm

Completeness Information and Its Application to Query Processing

Amihai Motro
1986 Very Large Data Bases Conference  
With completeness information it is possible to determine whether each ansivcr to a user query is complete, or whether any subsets of it are complete.  ...  With these methods, each relational algebra query can be n.ccompnnietl wi(.h a.n instantaneous verdict on its coml)letcness (or on the completcncss of some of its subsets).  ...  We have prcscntcd a new kind of database information, for specifying the subsets of the database which are .closed world". We have laid a formal basis, with Acknowledgements (,  ... 
dblp:conf/vldb/Motro86 fatcat:zegrqntrdbhmhpby545n2ii3wm

Query Answering over Complete Data with Conceptual Constraints

Nhung Ngo
2016 Proceedings of the 2016 on SIGMOD'16 PhD Symposium - SIGMOD'16 PhD  
Query answering over databases with conceptual constraints is an important problem in database theory.  ...  In this approach, databases are considered under open-world assumption which creates many issues including the necessity of restricting to only positive queries, and the failure of query composition.  ...  In other words, certain answer semantics gives no reasonable answers to non-monotone queries, as nicely summarised by [21] : answer to negative queries may be incomplete, and answering queries with aggregation  ... 
doi:10.1145/2926693.2929899 dblp:conf/sigmod/Ngo16 fatcat:o6f6vjbbnbeyrn5vzv4kdu54ny

Intelligent Query Processing in Malayalam

Raji Sukumar A, Babu Anto P
2013 International Journal on Computational Science & Applications  
NLQPS is a restricted domain system, deals with the natural Language Queries on time enquiry for different modes of transportation.  ...  After the knowledge level understanding of the query, the system triggers a reasoning process to determine the type of query and the result slots that are required.  ...  Since the early days of artificial intelligence in the 60's, researchers have been fascinated with answering natural language query.  ... 
doi:10.5121/ijcsa.2013.3206 fatcat:6hugrhubevbzha4afs3cm3cgwy

Getting more RDF support from relational databases

François Goasdoué, Ioana Manolescu, Alexandra Roatiş
2012 Proceedings of the 21st international conference companion on World Wide Web - WWW '12 Companion  
We introduce the database fragment of RDF, which extends the popular Description Logic fragment, in particular with support for incomplete information.  ...  Finally, we experimentally compare our query answering techniques using well-established datasets.  ...  The saturation of a database db with this restricted rule set is denoted db ∝ .  ... 
doi:10.1145/2187980.2188104 dblp:conf/www/GoasdoueMR12 fatcat:fl2qaxoaxfbh5gqciiwtthwuum

Small is Again Beautiful in Description Logics

Franz Baader, Carsten Lutz, Anni-Yasmin Turhan
2010 Künstliche Intelligenz  
The Description Logic (DL) research of the last 20 years was mainly concerned with increasing the expressive power of the employed description language without losing the ability of implementing highly-optimized  ...  Given an FOL query q, we denote the set of its answer tuples in the database I with q I .  ...  Interestingly, also in EL it is possible to implement query answering using a database system, though with a different approach than in DL-Lite (see the end of Section 3).  ... 
doi:10.1007/s13218-010-0004-8 fatcat:mqdsof4hcnfibgouuai35ibda4

Page 43 of Computational Linguistics Vol. 33, Issue 1 [page]

2007 Computational Linguistics  
The user’s question was converted into a database query, and the database output was given as the answer.  ...  question onto the corresponding database query.  ... 
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