35 citations · 126 across the 17 of their papers we have counts for
17 papers
Efficient Path Query Processing in Relational Database Systems
Diego Rivera Correa, Mirek Riedewald
Path queries are crucial for property graphs, and there is growing interest in queries that combine regular expressions over labels with constraints on property values of vertices…
Ranked Enumeration for Database Queries
Nikolaos Tziavelis, Wolfgang Gatterbauer, Mirek Riedewald
Ranked enumeration is a query-answering paradigm where the query answers are returned incrementally in order of importance (instead of returning all answers at once). Importance is…
Synthesizing Scoring Functions for Rankings Using Symbolic Gradient Descent
Zixuan Chen, Panagiotis Manolios, Mirek Riedewald
Given a relation and a ranking of its tuples, but no information about the ranking function, we are interested in synthesizing simple scoring functions that reproduce the ranking.…
Efficient Computation of Quantiles over Joins
Nikolaos Tziavelis, Nofar Carmeli, Wolfgang Gatterbauer +2
We present efficient algorithms for Quantile Join Queries, abbreviated as %JQ. A %JQ asks for the answer at a specified relative position (e.g., 50% for the median) under some orde…
SANTOS: Relationship-based Semantic Table Union Search
Aamod Khatiwada, Grace Fan, Roee Shraga +4
Existing techniques for unionable table search define unionability using metadata (tables must have the same or similar schemas) or column-based metrics (for example, the values in…
Principles of Query Visualization
Wolfgang Gatterbauer, Cody Dunne, H. V. Jagadish +1
Query Visualization (QV) is the problem of transforming a given query into a graphical representation that helps humans understand its meaning. This task is notably different from…
Any-k Algorithms for Enumerating Ranked Answers to Conjunctive Queries
Nikolaos Tziavelis, Wolfgang Gatterbauer, Mirek Riedewald
We study ranked enumeration for Conjunctive Queries (CQs) where the answers are ordered by a given ranking function (e.g., an ORDER BY clause in SQL). We develop "any-k" algorithms…
Relational Diagrams: a pattern-preserving diagrammatic representation of non-disjunctive Relational Queries
Wolfgang Gatterbauer, Cody Dunne, Mirek Riedewald
Analyzing relational languages by their logical expressiveness is well understood. Something not well understood or even formalized is the vague concept of relational query pattern…
DomainNet: Homograph Detection for Data Lake Disambiguation
Aristotelis Leventidis, Laura Di Rocco, Wolfgang Gatterbauer +2
Modern data lakes are deeply heterogeneous in the vocabulary that is used to describe data. We study a problem of disambiguation in data lakes: how can we determine if a data value…
Beyond Equi-joins: Ranking, Enumeration and Factorization
Nikolaos Tziavelis, Wolfgang Gatterbauer, Mirek Riedewald
We study theta-joins in general and join predicates with conjunctions and disjunctions of inequalities in particular, focusing on ranked enumeration where the answers are returned…
Tractable Orders for Direct Access to Ranked Answers of Conjunctive Queries
Nofar Carmeli, Nikolaos Tziavelis, Wolfgang Gatterbauer +2
We study the question of when we can provide direct access to the k-th answer to a Conjunctive Query (CQ) according to a specified order over the answers in time logarithmic in the…
Optimal Join Algorithms Meet Top-k
Nikolaos Tziavelis, Wolfgang Gatterbauer, Mirek Riedewald
Top-k queries have been studied intensively in the database community and they are an important means to reduce query cost when only the "best" or "most interesting" results are ne…
QueryVis: Logic-based diagrams help users understand complicated SQL queries faster
Aristotelis Leventidis, Jiahui Zhang, Cody Dunne +3
Understanding the meaning of existing SQL queries is critical for code maintenance and reuse. Yet SQL can be hard to read, even for expert users or the original creator of a query.…
Near-Optimal Distributed Band-Joins through Recursive Partitioning
Rundong Li, Wolfgang Gatterbauer, Mirek Riedewald
We consider running-time optimization for band-joins in a distributed system, e.g., the cloud. To balance load across worker machines, input has to be partitioned, which causes dup…
Optimal Algorithms for Ranked Enumeration of Answers to Full Conjunctive Queries
Nikolaos Tziavelis, Deepak Ajwani, Wolfgang Gatterbauer +2
We study ranked enumeration of join-query results according to very general orders defined by selective dioids. Our main contribution is a framework for ranked enumeration over a c…
Any-k: Anytime Top-k Tree Pattern Retrieval in Labeled Graphs
Xiaofeng Yang, Deepak Ajwani, Wolfgang Gatterbauer +3
Many problems in areas as diverse as recommendation systems, social network analysis, semantic search, and distributed root cause analysis can be modeled as pattern search on label…
ILP Modulo Data
Panagiotis Manolios, Vasilis Papavasileiou, Mirek Riedewald
The vast quantity of data generated and captured every day has led to a pressing need for tools and processes to organize, analyze and interrelate this data. Automated reasoning an…