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Precise complexity analysis for efficient datalog queries

K. Tuncay Tekle, Yanhong A. Liu
2010 Proceedings of the 12th international ACM SIGPLAN symposium on Principles and practice of declarative programming - PPDP '10  
Given a set of Datalog rules, facts, and a query, answers to the query can be inferred bottom-up starting with the facts or top-down starting with the query.  ...  For efficiently answering the query, topdown evaluation is extended with tabling that stores the results of the subqueries encountered, and bottom-up evaluation is done on rules transformed based on demand  ...  We thank David Warren and Michael Kifer for many helpful discussions on the implementation of XSB, and on logic programming in general.  ... 
doi:10.1145/1836089.1836094 dblp:conf/ppdp/TekleL10 fatcat:ozhviyyfirbprkuvdcacvwhkgm

SPARQL-to-SQL Query Translation: Bottom-Up or Top-Down?

Andrey Kashlev, Artem Chebotko
2011 2011 IEEE International Conference on Services Computing  
While it can be expected that relational query optimizers produce identical query execution plans for semantically equivalent bottom-up and top-down queries, is this usually the case in practice?  ...  Existing algorithms translate SPARQL queries to SQL using either bottom-up or top-down strategy and result in semantically equivalent but syntactically different relational queries.  ...  While there exist both bottom-up and top-down strategies that generate equivalent SQL queries with nested sub-queries, we explore a simple strategy that generates fully flat SQL queries.  ... 
doi:10.1109/scc.2011.79 dblp:conf/IEEEscc/KashlevC11 fatcat:q3nw2hfezffktie5kexdwde2rq

Towards a New Step of Logic Paradigm [chapter]

Kazuhiro FUCHI
1990 Deductive and Object-Oriented Databases  
bottom-up processing.  ...  Then, we reconsider query evaluation methods for recursive databases.  ...  This procedure performs top-down reasoning but it is specified by a bottom-up meta-interpreter, i.e., in a meta-language by means of rules intended for bottom-up processing.  ... 
doi:10.1016/b978-0-444-88433-6.50008-3 fatcat:jgqxvfczlvgargtfqxaz6engrm

Query Evaluation in Recursive Databases: Bottom-up and Top-down Reconciled [chapter]

François Bry
1990 Deductive and Object-Oriented Databases  
BiT ' Query evaluation in recursive databases bottom-up from the database rules and facts. Therefore, they do not use the constants occurring in the queries for restricting the search space.  ...  We rely on bottom-up meta-interpretation for formalizing the Backward Fixpoint Procedure, i.e. we specify a top-down evaluation of the database rules in a meta-language by means of rules intended for bottom-up  ...  bottom-up evaluation is desired.  ... 
doi:10.1016/b978-0-444-88433-6.50010-1 fatcat:iqqylekna5gfrmm54t7sz3jzim

Query evaluation in recursive databases: bottom-up and top-down reconciled

François Bry
1990 Data & Knowledge Engineering  
BiT ' Query evaluation in recursive databases bottom-up from the database rules and facts. Therefore, they do not use the constants occurring in the queries for restricting the search space.  ...  We rely on bottom-up meta-interpretation for formalizing the Backward Fixpoint Procedure, i.e. we specify a top-down evaluation of the database rules in a meta-language by means of rules intended for bottom-up  ...  bottom-up evaluation is desired.  ... 
doi:10.1016/0169-023x(90)90017-8 fatcat:uthlb7gvcbdvxpwkxdttaea6lu

More efficient datalog queries

K. Tuncay Tekle, Yanhong A. Liu
2011 Proceedings of the 2011 international conference on Management of data - SIGMOD '11  
Given a set of Datalog rules, facts, and a query, answers to the query can be inferred bottom-up starting with the facts or top-down starting with the query.  ...  of bottom-up evaluation after this transformation is equal to the the time complexity of top-down evaluation with subsumptive tabling.  ...  We call bottom-up evaluation extended with inflationary semantics inflationary bottom-up evaluation.  ... 
doi:10.1145/1989323.1989393 dblp:conf/sigmod/TekleL11 fatcat:tm5fnlbrnvh35dre3yj4pd6rou

Extended Magic for Negation: Efficient Demand-Driven Evaluation of Stratified Datalog with Precise Complexity Guarantees

K. Tuncay Tekle, Yanhong A. Liu
2019 Electronic Proceedings in Theoretical Computer Science  
Given a set of Datalog rules, facts, and a query, answers to the query can be inferred bottom-up starting from the facts or top-down starting from the query.  ...  For efficiency, top-down evaluation is extended with memoization of inferred facts, and bottom-up evaluation is performed after transformations to make rules driven by the demand from the query.  ...  Given a set of Datalog rules, facts, and a query, answers to the query can be inferred using bottom-up evaluation starting with the facts or top-down evaluation starting with the query.  ... 
doi:10.4204/eptcs.306.28 fatcat:qmt3s2tf7bc3tmhdhjxb5vhfsm

Abstract filters

Byeong-Mo Chang, Kwang-Moo Choe, Roberto Giacobazzi
1994 Proceedings of the 1994 ACM symposium on Applied computing - SAC '94  
Bottom-uo evaluation of logic programs may be i t.~efficient as it may generate many irrelevant facts to a given query.  ...  The filtering strategy prevents Fossible irrelevant facts from being processed in the bottom-up evaluation on system graphs.  ...  However, bottom-up query evaluation may be inefficient since it may generate many irrelevant facts to a given query.  ... 
doi:10.1145/326619.326788 dblp:conf/sac/ChangCG94 fatcat:bu4oufzpxzbuzf2uxdvklaluj4

Top-down and Bottom-up Evaluation Procedurally Integrated

DAVID S. WARREN
2018 Theory and Practice of Logic Programming  
This paper shows how to introduce into tabled logic program evaluation a bottom-up component, whose procedural intuition is the initialization of a data structure, in which a relation is initially computed  ...  AbstractThis paper describes how the Logic Programming System XSB combines top-down and bottom-up computation through the mechanisms of variant tabling and subsumptive tabling with abstraction, respectively.It  ...  Subsumptive tabling with abstraction has the properties of bottom-up evaluation, described above, of generating a full table once and then using the resulting table for subsequent queries.  ... 
doi:10.1017/s1471068418000194 fatcat:kewfla4zpjeixlm4akia3duzni

Depth-bounded bottom-up evaluation of logic programs

Jan Chomicki
1995 The Journal of Logic Programming  
We present here a depth-bounded bottom-up evaluation algorithm for logic programs.  ...  We also show that universal safety (finiteness of query answers for any database) is decidable for Datalogns.  ...  First, can bottom-up evaluation of finite-answer queries be always made to terminate?  ... 
doi:10.1016/0743-1066(94)00030-a fatcat:6e67ebespzcybonkkpdtbimq44

Magic templates: a spellbinding approach to logic programs

Raghu Ramakrishnan
1991 The Journal of Logic Programming  
and bottom-up evaluation strategies.  ...  D We consider a bottom-up query-evaluation scheme in which facts of relations are allowed to have nonground terms.  ... 
doi:10.1016/0743-1066(91)90026-l fatcat:wezmcdj64bb2be5lhwe7m5kaqy

Evaluating XML-extended OLAP queries based on a physical algebra

Xuepeng Yin, Torben Bach Pedersen
2004 Proceedings of the 7th ACM international workshop on Data warehousing and OLAP - DOLAP '04  
In this paper, we extend previous work on the logical federation of OLAP and XML data sources by presenting a simplified query semantics, a physical query algebra and a robust OLAP-XML query engine.  ...  Performance experiments with a prototypical implementation suggest that the performance for OLAP-XML federations is comparable to queries on physically integrated data.  ...  The plan is evaluated in a bottom-up fashion.  ... 
doi:10.1145/1031763.1031778 dblp:conf/dolap/YinP04 fatcat:3o5gtumpcrcbnoxboclihhmevm

Maintenance of Recursive Views [chapter]

Suzanne W. Dietrich
2017 Encyclopedia of Database Systems  
A disadvantage of this bottom-up approach for evaluating a query is that the entire view is computed even when a query may be asking for a small subset of the data.  ...  In a bottom-up approach to evaluating a rule, the known collection of facts is used to satisfy the subgoals on the right-hand side of the rule, generating new facts for the relation on the left-hand side  ...  PF starts by propagating the edge deletion using the nonrecursive rule, which generates a potential deletion of reach(e,f).  ... 
doi:10.1007/978-1-4899-7993-3_842-2 fatcat:fbblwrhi6ndjpdh75nbxr2x4nq

Pushing constraint selections

Divesh Srivastava, Raghu Ramakrishnan
1993 The Journal of Logic Programming  
D Bottom-up evaluation of a program-query pair in a constraint query language often computes only ground facts. Constraints do not contribute to answers, but are used only to prune derivations.  ...  In general, constraint facts are computed, making the resulting evaluation more expensive.  ...  ground facts, if the bottom-up evaluation of P does so, and the bottom-up evaluation of P' computes, in general, fewer facts than the bottomup evaluation of P.  ... 
doi:10.1016/0743-1066(93)90048-l fatcat:tlua2vpnuncftcr5wvcwywroei

A Framework for Goal-Directed Bottom-Up Evaluation of Functional Logic Programs [chapter]

Jesús M. Almendros-Jiménez, Antonio Becerra-Terón
2001 Lecture Notes in Computer Science  
The program is evaluated using bottom-up evaluation until no new facts are generated or the answer to the query is found.  ...  The goal-directed bottom-up evaluation generates the subset of the Herbrand model of the program relevant to the query.  ...  As in the logic paradigm, the bottom-up evaluation will consist in a magic transformation for a given program-query into a magic program-query for which the bottom-up evaluation will simulate the top-down  ... 
doi:10.1007/3-540-44716-4_10 fatcat:dn5l4rfuyzenxfwhoca4q7l5za
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