Graph minors. V. Excluding a planar graph
Journal of Combinatorial Theory Series B
On the complexity of H-coloring
Journal of Combinatorial Theory Series B
Finding minimally weighted subgraphs
WG '90 Proceedings of the 16th international workshop on Graph-theoretic concepts in computer science
Discrete Mathematics - Algebraic graph theory; a volume dedicated to Gert Sabidussi
Linear programming without the matrix
STOC '93 Proceedings of the twenty-fifth annual ACM symposium on Theory of computing
Quickly excluding a planar graph
Journal of Combinatorial Theory Series B
Fixed-parameter tractability and completeness II: on completeness for W[1]
Theoretical Computer Science
Fixed-Parameter Tractability and Completeness I: Basic Results
SIAM Journal on Computing
On the expressive power of Datalog: tools and a case study
Selected papers of the 9th annual ACM SIGACT-SIGMOD-SIGART symposium on Principles of database systems
Graph minors. XII: distance on a surface
Journal of Combinatorial Theory Series B
Conjunctive-query containment and constraint satisfaction
PODS '98 Proceedings of the seventeenth ACM SIGACT-SIGMOD-SIGART symposium on Principles of database systems
Constraint satisfaction and database theory: a tutorial
PODS '00 Proceedings of the nineteenth ACM SIGMOD-SIGACT-SIGART symposium on Principles of database systems
When is the evaluation of conjunctive queries tractable?
STOC '01 Proceedings of the thirty-third annual ACM symposium on Theory of computing
The complexity of maximal constraint languages
STOC '01 Proceedings of the thirty-third annual ACM symposium on Theory of computing
Foundations of Databases: The Logical Level
Foundations of Databases: The Logical Level
Query evaluation via tree-decompositions
Journal of the ACM (JACM)
A Dichotomy Theorem for Constraints on a Three-Element Set
FOCS '02 Proceedings of the 43rd Symposium on Foundations of Computer Science
Conjunctive Query Containment Revisited
ICDT '97 Proceedings of the 6th International Conference on Database Theory
Constraint Satisfaction, Bounded Treewidth, and Finite-Variable Logics
CP '02 Proceedings of the 8th International Conference on Principles and Practice of Constraint Programming
Tractable conservative Constraint Satisfaction Problems
LICS '03 Proceedings of the 18th Annual IEEE Symposium on Logic in Computer Science
Optimal implementation of conjunctive queries in relational data bases
STOC '77 Proceedings of the ninth annual ACM symposium on Theory of computing
Robbers, marshals, and guards: game theoretic and logical characterizations of hypertree width
Journal of Computer and System Sciences - Special issu on PODS 2001
The Complexity of Homomorphism and Constraint Satisfaction Problems Seen from the Other Side
FOCS '03 Proceedings of the 44th Annual IEEE Symposium on Foundations of Computer Science
The complexity of counting homomorphisms seen from the other side
Theoretical Computer Science
Generalized Majority-Minority Operations are Tractable
LICS '05 Proceedings of the 20th Annual IEEE Symposium on Logic in Computer Science
Constraint solving via fractional edge covers
SODA '06 Proceedings of the seventeenth annual ACM-SIAM symposium on Discrete algorithm
Parameterized Complexity Theory (Texts in Theoretical Computer Science. An EATCS Series)
Parameterized Complexity Theory (Texts in Theoretical Computer Science. An EATCS Series)
A unified theory of structural tractability for constraint satisfaction and spread cut decomposition
IJCAI'05 Proceedings of the 19th international joint conference on Artificial intelligence
Parameterized Complexity
Majority constraints have bounded pathwidth duality
European Journal of Combinatorics
Non-dichotomies in Constraint Satisfaction Complexity
ICALP '08 Proceedings of the 35th international colloquium on Automata, Languages and Programming, Part II
Structural Tractability of Propagated Constraints
CP '08 Proceedings of the 14th international conference on Principles and Practice of Constraint Programming
Approximating fractional hypertree width
SODA '09 Proceedings of the twentieth Annual ACM-SIAM Symposium on Discrete Algorithms
Uniform Constraint Satisfaction Problems and Database Theory
Complexity of Constraints
A note on some collapse results of valued constraints
Information Processing Letters
Tricolorable torus knots are NP-complete
Proceedings of the 47th Annual Southeast Regional Conference
Counting Subgraphs via Homomorphisms
ICALP '09 Proceedings of the 36th International Colloquium on Automata, Languages and Programming: Part I
Tree Projections: Game Characterization and Computational Aspects
Graph Theory, Computational Intelligence and Thought
New Plain-Exponential Time Classes for Graph Homomorphism
CSR '09 Proceedings of the Fourth International Computer Science Symposium in Russia on Computer Science - Theory and Applications
Constraint satisfaction, databases, and logic
IJCAI'03 Proceedings of the 18th international joint conference on Artificial intelligence
A note on width-parameterized SAT: An exact machine-model characterization
Information Processing Letters
TABLEAUX '09 Proceedings of the 18th International Conference on Automated Reasoning with Analytic Tableaux and Related Methods
Approximating fractional hypertree width
ACM Transactions on Algorithms (TALG)
Generalizing constraint satisfaction on trees: Hybrid tractability and variable elimination
Artificial Intelligence
Bounded tree-width and CSP-related problems
ISAAC'07 Proceedings of the 18th international conference on Algorithms and computation
Constraint representations and structural tractability
CP'09 Proceedings of the 15th international conference on Principles and practice of constraint programming
CP'09 Proceedings of the 15th international conference on Principles and practice of constraint programming
Tractable hypergraph properties for constraint satisfaction and conjunctive queries
Proceedings of the forty-second ACM symposium on Theory of computing
Proceedings of the twenty-ninth ACM SIGMOD-SIGACT-SIGART symposium on Principles of database systems
Causal graphs and structurally restricted planning
Journal of Computer and System Sciences
Constraint satisfaction problems and global cardinality constraints
Communications of the ACM
Pure Nash equilibria: complete characterization of hard and easy graphical games
Proceedings of the 9th International Conference on Autonomous Agents and Multiagent Systems: volume 1 - Volume 1
Constraint satisfaction with succinctly specified relations
Journal of Computer and System Sciences
The Necessity of Bounded Treewidth for Efficient Inference in Bayesian Networks
Proceedings of the 2010 conference on ECAI 2010: 19th European Conference on Artificial Intelligence
On brambles, grid-like minors, and parameterized intractability of monadic second-order logic
SODA '10 Proceedings of the twenty-first annual ACM-SIAM symposium on Discrete Algorithms
Database theory: query languages
Algorithms and theory of computation handbook
A new hybrid tractable class of soft constraint problems
CP'10 Proceedings of the 16th international conference on Principles and practice of constraint programming
Structural tractability of enumerating CSP solutions
CP'10 Proceedings of the 16th international conference on Principles and practice of constraint programming
Hybrid tractability of valued constraint problems
Artificial Intelligence
CP'11 Proceedings of the 17th international conference on Principles and practice of constraint programming
Structural tractability of constraint optimization
CP'11 Proceedings of the 17th international conference on Principles and practice of constraint programming
The complexity of conservative valued CSPs
Proceedings of the twenty-third annual ACM-SIAM symposium on Discrete Algorithms
Computing hypergraph width measures exactly
Information Processing Letters
Journal of Computer and System Sciences
Constraint optimization problems and bounded tree-width revisited
CPAIOR'12 Proceedings of the 9th international conference on Integration of AI and OR Techniques in Constraint Programming for Combinatorial Optimization Problems
Decomposing Quantified Conjunctive (or Disjunctive) Formulas
LICS '12 Proceedings of the 2012 27th Annual IEEE/ACM Symposium on Logic in Computer Science
Tractable triangles and cross-free convexity in discrete optimisation
Journal of Artificial Intelligence Research
Datalog and constraint satisfaction with infinite templates
Journal of Computer and System Sciences
A characterisation of the complexity of forbidding subproblems in binary Max-CSP
CP'12 Proceedings of the 18th international conference on Principles and Practice of Constraint Programming
The exponential time hypothesis and the parameterized clique problem
IPEC'12 Proceedings of the 7th international conference on Parameterized and Exact Computation
The tractability of CSP classes defined by forbidden patterns
Journal of Artificial Intelligence Research
Structural tractability of counting of solutions to conjunctive queries
Proceedings of the 16th International Conference on Database Theory
The complexity of conservative valued CSPs
Journal of the ACM (JACM)
The fine classification of conjunctive queries and parameterized logarithmic space complexity
Proceedings of the 32nd symposium on Principles of database systems
Tractable counting of the answers to conjunctive queries
Journal of Computer and System Sciences
The complexity of finite-valued CSPs
Proceedings of the forty-fifth annual ACM symposium on Theory of computing
An algebraic characterization of testable boolean CSPs
ICALP'13 Proceedings of the 40th international conference on Automata, Languages, and Programming - Volume Part I
Block-Sorted quantified conjunctive queries
ICALP'13 Proceedings of the 40th international conference on Automata, Languages, and Programming - Volume Part II
Locally constrained homomorphisms on graphs of bounded treewidth and bounded degree
FCT'13 Proceedings of the 19th international conference on Fundamentals of Computation Theory
The complexity of weighted counting for acyclic conjunctive queries
Journal of Computer and System Sciences
Tractable Hypergraph Properties for Constraint Satisfaction and Conjunctive Queries
Journal of the ACM (JACM)
On the complexity of existential positive queries
ACM Transactions on Computational Logic (TOCL)
Theoretical Computer Science
Hi-index | 0.02 |
We give a complexity theoretic classification of homomorphism problems for graphs and, more generally, relational structures obtained by restricting the left hand side structure in a homomorphism. For every class C of structures, let HOM(C,−) be the problem of deciding whether a given structure A ∈C has a homomorphism to a given (arbitrary) structure ß. We prove that, under some complexity theoretic assumption from parameterized complexity theory, HOM(C,−) is in polynomial time if and only if C has bounded tree width modulo homomorphic equivalence. Translated into the language of constraint satisfaction problems, our result yields a characterization of the tractable structural restrictions of constraint satisfaction problems. Translated into the language of database theory, it implies a characterization of the tractable instances of the evaluation problem for conjunctive queries over relational databases.