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On Monotonic Determinacy and Rewritability for Recursive Queries and Views

Michael Benedikt, Stanislav Kikot, Piotr Ostropolski-Nalewaja, Miguel Romero
2020 Proceedings of the 39th ACM SIGMOD-SIGACT-SIGAI Symposium on Principles of Database Systems  
We investigate the situation for views and queries in the recursive query language Datalog.  ...  In the case of relational algebra views and queries, monotonic determinacy coincides with rewritability as a union of conjunctive queries, and it is decidable in important special cases, such as for CQ  ...  For specialized recursive queries and views over a graph schema, the regular path queries, both the determinacy and monotonic determinacy problem have been studied.  ... 
doi:10.1145/3375395.3387661 dblp:conf/pods/BenediktKO020 fatcat:qlmunflhx5dbli6qf5lyvzl5ue

On monotonic determinacy and rewritability for recursive queries and views [article]

Michael Benedikt, Stanislav Kikot, Piotr Ostropolski-Nalewaja, and Miguel Romero
2020 arXiv   pre-print
We investigate the situation for views and queries in the recursive query language Datalog.  ...  In the case of relational algebra views and queries, monotonic determinacy coincides with rewritability as a union of conjunctive queries, and it is decidable in important special cases, such as for CQ  ...  For specialized recursive queries and views over a graph schema, the regular path queries, both the determinacy and monotonic determinacy problem have been studied.  ... 
arXiv:2003.05898v1 fatcat:wan4gqsbpjdojhllie3lrj2dii

Views and queries

Luc Segoufin, Victor Vianu
2005 Proceedings of the twenty-fourth ACM SIGMOD-SIGACT-SIGART symposium on Principles of database systems - PODS '05  
CQ is complete for CQ-to-CQ rewritings; 2. for CQ views V and queries Q, V Q on finite instances iff V Q on unrestricted instances; and, 3. for CQ views V and queries Q, the query Q V is monotonic.  ...  The results concern decidability of determinacy for various view and query languages, as well as the power required of complete rewriting languages.  ...  CQ is complete for CQ-to-CQ rewritings; 2. for CQ views V and queries Q, V Q on finite instances iff V Q on unrestricted instances; and, 3 . for CQ views V and queries Q for which V Q, the query Q V is  ... 
doi:10.1145/1065167.1065174 dblp:conf/pods/SegoufinV05 fatcat:zgvpqw5blregbdskpny3dn24ii

Query Processing in Data Integration

Paolo Guagliardo, Piotr Wieczorek, Marc Herbstritt
2013 Dagstuhl Publications  
A rewriting Q r ∈ L r of a query Q ∈ L q under exact views V is L r -maximal iff, there exists no rewriting Q r ∈ L r of Q under V such that Q r V R (D) ⊃ Q r V R (D) for some database D.  ...  A rewriting Q r ∈ L r of a query Q ∈ L q under sound views V is L r -maximal iff, there is no rewriting Q r ∈ L r of Q under V such that, for some V-extension E which is sound w.r.t. some database D, it  ...  In fact, as shown in [47] , determinacy for PF queries and views is 2EXPTIME-complete and PF is complete for PF-to-PF rewritings.  ... 
doi:10.4230/dfu.vol5.10452.129 dblp:conf/dagstuhl/GuagliardoW13 fatcat:2bqbnhu3wbe3rcvsck6aqzr3em

Can One Escape Red Chains? Regular Path Queries Determinacy is Undecidable [article]

Grzegorz Głuch, Jerzy Marcinkowski, Piotr Ostropolski-Nalewaja
2018 arXiv   pre-print
Q_k} and for another query Q_0 we say that Q determines Q_0 if -- informally speaking -- for every database D, the information contained in the views Q( D) is sufficient to compute Q_0( D).  ...  Query Determinacy Problem is the problem of deciding, for given Q and Q_0, whether Q determines Q_0. Many versions of this problem, for different query languages, were studied in database theory.  ...  However, [CGLV02a] also provides an example where a regular path view determines a regular path query in a non-monotone way showing that, in this setting, determinacy does not coincide with monotone  ... 
arXiv:1802.01554v1 fatcat:w3fte6utp5cbtl3miqrm6ac6aa

Determinacy and query rewriting for conjunctive queries and views

Foto N. Afrati
2011 Theoretical Computer Science  
We consider the case where query and views are defined by conjunctive queries and investigate the question: If a view set V determines a query Q , is there an equivalent rewriting of Q using V?  ...  Interestingly, we identify a class of conjunctive queries, CQ path , for which a view set can produce equivalent rewritings for "almost all" queries which are determined by this view set.  ...  No monotonic language is complete for CQ-to-CQ rewriting, e.g., CQ̸ = or UCQ or Datalog̸ = will not do. Determinacy is undecidable for UCQ views and queries.  ... 
doi:10.1016/j.tcs.2010.12.031 fatcat:35i7szpbnndojcq4hyzdrp6z6u

How Can Reasoners Simplify Database Querying (And Why Haven't They Done It Yet)?

Michael Benedikt
2018 Proceedings of the 35th ACM SIGMOD-SIGACT-SIGAI Symposium on Principles of Database Systems - SIGMOD/PODS '18  
The purpose of this article is to reflect on the use of reasoning for rewriting and simplifying relational database queries.  ...  critique of prior work from the point of view of practice.  ...  I want to express my deep gratitude to Marcelo Arenas, Michaël Cadilhac, Phokion Kolaitis, Dan Olteanu, and Victor Vianu for extensive feedback on this work.  ... 
doi:10.1145/3196959.3196989 dblp:conf/pods/Benedikt18 fatcat:fmx4gidgbzb6fpxtvrsy4eyskm

Generating low-cost plans from proofs

Michael Benedikt, Balder ten Cate, Efthymia Tsamoura
2014 Proceedings of the 33rd ACM SIGMOD-SIGACT-SIGART symposium on Principles of database systems - PODS '14  
The key idea of our method is to move from a search for a plan to a search for a proof that a query is answerable, and then generate a plan from a proof.  ...  We then provide algorithms for schemas based on tuple-generating dependencies. These algorithms perform interpolation, but generate plans directly.  ...  Q is monotone in Q 1 . . . Q n iff there is a USPJrewriting of Q in terms of Q 1 . . . Q n . That is, queries monotone in a set of views are USPJ-rewritable.  ... 
doi:10.1145/2594538.2594550 dblp:conf/pods/BenediktCT14 fatcat:fq3n4rafljd6pmnvjjzw5pz4pq

The Hunt for a Red Spider: Conjunctive Query Determinacy Is Undecidable

Tomasz Gogacz, Jerzy Marcinkowski
2015 2015 30th Annual ACM/IEEE Symposium on Logic in Computer Science  
We solve a well known, long-standing open problem in relational databases theory, showing that the conjunctive query determinacy problem (in its "unrestricted" version) is undecidable.  ...  using the rule ➁A and notice the recursion.  ...  And we are given another conjunctive query Q 0 . Will we be able to compute Q 0 only using the available views? The answer depends on whether the queries Q 1 , Q 2 , . . . Q k determine query Q 0 .  ... 
doi:10.1109/lics.2015.35 dblp:conf/lics/GogaczM15 fatcat:7kh635ymcbemzi3iwvklzewclq

Some Model Theory of Guarded Negation [article]

Vince Barany, Michael Benedikt, Balder ten Cate
2020 arXiv   pre-print
Our results include effective preservation theorems for GNFO, effective Craig Interpolation and Beth Definability results, and the ability to express the certain answers of queries with respect to a large  ...  This version of the paper contains streamlined and corrected versions of results concerning entailment of a conjunctive query from a set of ground facts and a theory consisting of GNFO sentences of a special  ...  We want to thank Maarten Marx for helpful discussions and help in verifying the counterexamples of Section 4.  ... 
arXiv:2005.06299v2 fatcat:awujhhdh6bgrrgs3xu3v7igz4u

Blockaid: Data Access Policy Enforcement for Web Applications [article]

Wen Zhang, Eric Sheng, Michael Chang, Aurojit Panda, Mooly Sagiv, Scott Shenker
2022 arXiv   pre-print
It verifies policy compliance using SMT solvers and generalizes and caches previous compliance decisions for better performance.  ...  It intercepts database queries from the application, attempts to verify that each query is policy-compliant, and blocks queries that are not.  ...  Acknowledgments We are grateful to Alin Deutsch and Victor Vianu for the many discussions about query determinacy, and to Nikolaj Bjørner, Alvin Cheung, Vivian Fang, and members of the Berkeley Net-Sys  ... 
arXiv:2205.06911v2 fatcat:2feflzmi7ngzbhdb75qq7h5kai

Generating Plans from Proofs

Michael Benedikt, Balder Ten Cate, Efthymia Tsamoura
2016 ACM Transactions on Database Systems  
On the other hand, the views are clearly sufficient to answer a query asking for the last names of students whose advisor has last name Jones, and we can reformulate that query as a selection over Student  ...  on profname "Jones".2 Naturally, constraints need not come from views.  ...  Definition 4.5 (Access monotonic determinacy).  ... 
doi:10.1145/2847523 fatcat:szrzwhessvhs5coqcsebtwqeva

Timed Default Concurrent Constraint Programming

VIJAY SARASWAT, RADHA JAGADEESAN, VINEET GUPTA
1996 Journal of symbolic computation  
for untimed concurrent constraint programming (CCP).  ...  We identify a basic set of combinators (that constitute the Timed Default cc programming framework), and provide a constructive operational semantics (implemented by us as an interpreter) for which the  ...  By determinacy of Z, v = v 0 , thus Z 2 = Z 1 . 2 The soundness and completeness of the logic for recursion free Default ccprograms without hiding is shown as follows: Proof.  ... 
doi:10.1006/jsco.1996.0064 fatcat:vkqmw4v4tnfczhop4kc76hdheu

Subject index volumes 1–200

1999 Theoretical Computer Science  
left -grammar, 758 V-gates, 702 in monotone networks, 186 Vbgvolgyi, Flilbp and -, 2937 in a database scheme, Berge-acyclic -, 686 update, 3802 views of conditioned-tables, 1457 Vincent theorem.  ...  3603 polylog space, 5 18 polynomial-rime, 2676 primitive recursion on trees, 1461 recursion, 1037 simultaneous rigid E-unification, 3295 problem, 3295 simultaneous space-reduction and speed-up  ... 
doi:10.1016/s0304-3975(98)00319-3 fatcat:s22ud3iiqjht7lfbtc3zctk7zm

Some global optimizations for a PROLOG compiler

C.S. Mellish
1985 The Journal of Logic Programming  
AN EXAMPLE OF STATIC ANALYSIS-DETECTING DETERMINACY A PROLOG program can be viewed as a set of equations specifying for each predicate what instances can be inferred.  ...  We have a working program for inferring determinacy which works as described and with this extension.  ... 
doi:10.1016/0743-1066(85)90004-4 fatcat:h75c2ruydravfpyeepkklterpu
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