Zobrazeno 1 - 10
of 131
pro vyhledávání: '"KOUTRIS, PARASCHOS"'
Join evaluation is one of the most fundamental operations performed by database systems and arguably the most well-studied problem in the Database community. A staggering number of join algorithms have been developed, and commercial database engines
Externí odkaz:
http://arxiv.org/abs/2406.07847
Datalog is a powerful yet elegant language that allows expressing recursive computation. Although Datalog evaluation has been extensively studied in the literature, so far, only loose upper bounds are known on how fast a Datalog program can be evalua
Externí odkaz:
http://arxiv.org/abs/2403.12436
We study the data complexity of consistent query answering (CQA) on databases that may violate the primary key constraints. A repair is a maximal subset of the database satisfying the primary key constraints. For a Boolean query q, the problem CERTAI
Externí odkaz:
http://arxiv.org/abs/2310.19642
In this paper, we study the complexity of evaluating Conjunctive Queries with negation (\cqneg). First, we present an algorithm with linear preprocessing time and constant delay enumeration for a class of CQs with negation called free-connex signed-a
Externí odkaz:
http://arxiv.org/abs/2310.05385
We study the data complexity of consistent query answering (CQA) on databases that may violate the primary key constraints. A repair is a maximal consistent subset of the database. For a Boolean query $q$, the problem $\mathsf{CERTAINTY}(q)$ takes a
Externí odkaz:
http://arxiv.org/abs/2309.15270
Autor:
Koutris, Paraschos, Deep, Shaleen
Many problems in static program analysis can be modeled as the context-free language (CFL) reachability problem on directed labeled graphs. The CFL reachability problem can be generally solved in time $O(n^3)$, where $n$ is the number of vertices in
Externí odkaz:
http://arxiv.org/abs/2308.09284
This paper presents predicate transfer, a novel method that optimizes join performance by pre-filtering tables to reduce the join input sizes. Predicate transfer generalizes Bloom join, which conducts pre-filtering within a single join operation, to
Externí odkaz:
http://arxiv.org/abs/2307.15255
We study the fine-grained complexity of evaluating Boolean Conjunctive Queries and their generalization to sum-of-product problems over an arbitrary semiring. For these problems, we present a general semiring-oblivious reduction from the k-clique pro
Externí odkaz:
http://arxiv.org/abs/2304.14557
In this paper, we investigate space-time tradeoffs for answering conjunctive queries with access patterns (CQAPs). The goal is to create a space-efficient data structure in an initial preprocessing phase and use it for answering (multiple) queries in
Externí odkaz:
http://arxiv.org/abs/2304.06221