Decidable optimization problems for database logic programs
STOC '88 Proceedings of the twentieth annual ACM symposium on Theory of computing
Answering queries using templates with binding patterns (extended abstract)
PODS '95 Proceedings of the fourteenth ACM SIGACT-SIGMOD-SIGART symposium on Principles of database systems
Managing semantic heterogeneity in databases: a theoretical prospective
PODS '97 Proceedings of the sixteenth ACM SIGACT-SIGMOD-SIGART symposium on Principles of database systems
Query optimization in the presence of limited access patterns
SIGMOD '99 Proceedings of the 1999 ACM SIGMOD international conference on Management of data
Query containment for data integration systems
PODS '00 Proceedings of the nineteenth ACM SIGMOD-SIGACT-SIGART symposium on Principles of database systems
Answering queries with useful bindings
ACM Transactions on Database Systems (TODS)
Foundations of Databases: The Logical Level
Foundations of Databases: The Logical Level
Information Integration Using Logical Views
ICDT '97 Proceedings of the 6th International Conference on Database Theory
On Answering Queries in the Presence of Limited Access Patterns
ICDT '01 Proceedings of the 8th International Conference on Database Theory
Optimized Querying of Integrated Data over the Web
Proceedings of the IFIP TC8 / WG8.1 Working Conference on Engineering Information Systems in the Internet Context
Answering queries using views: A survey
The VLDB Journal — The International Journal on Very Large Data Bases
Optimal implementation of conjunctive queries in relational data bases
STOC '77 Proceedings of the ninth annual ACM symposium on Theory of computing
Query Planning with Limited Source Capabilities
ICDE '00 Proceedings of the 16th International Conference on Data Engineering
Computing complete answers to queries in the presence of limited access patterns
The VLDB Journal — The International Journal on Very Large Data Bases
Processing first-order queries under limited access patterns
PODS '04 Proceedings of the twenty-third ACM SIGMOD-SIGACT-SIGART symposium on Principles of database systems
Data exchange: semantics and query answering
Theoretical Computer Science - Database theory
Rewriting queries using views with access patterns under integrity constraints
ICDT'05 Proceedings of the 10th international conference on Database Theory
Semantic Annotations and Querying of Web Data Sources
OTM '09 Proceedings of the Confederated International Conferences, CoopIS, DOA, IS, and ODBASE 2009 on On the Move to Meaningful Internet Systems: Part I
Proceedings of the 13th International Conference on Extending Database Technology
Determining relevance of accesses at runtime
Proceedings of the thirtieth ACM SIGMOD-SIGACT-SIGART symposium on Principles of database systems
ICALP'12 Proceedings of the 39th international colloquium conference on Automata, Languages, and Programming - Volume Part II
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Access limitations may occur when querying data sources over the web or heterogeneous data sources presented as relational tables: this happens, for instance, in Data Exchange and Integration, Data Warehousing, and Web Information Systems. Access limitations force certain attributes to be selected in order to access the tables. It is known that evaluating a conjunctive query under such access restrictions amounts to evaluating a possibly recursive Datalog program. We address the problem of checking containment of conjunctive queries under access limitations, which is highly relevant in query optimization. Checking containment in such a setting would amount to checking containment of recursive Datalog programs of a certain class, while, for general Datalog programs, this problem is undecidable. We propose a decision procedure for query containment based on the novel notion of crayfish-chase, showing that containment can be decided in co-nexptime, which improves upon the known bound of 2exptime. Moreover, by means of a direct proof, our technique provides a new insight into the structure of the problem.