Tuple

About: Tuple is a research topic. Over the lifetime, 6513 publications have been published within this topic receiving 146057 citations. The topic is also known as: tuple & ordered tuplet.

S4: Top-k Spreadsheet-Style Search for Query Discovery

Abstract: An enterprise information worker is often aware of a few example tuples that should be present in the output of the query. Query discovery systems have been developed to discover project-join queries that contain the given example tuples in their output. However, they require the output to exactly contain all the example tuples and do not perform any ranking. To address this limitation, we study the problem of efficiently discovering top-k project join queries which approximately contain the given example tuples in their output. We extend our algorithms to incrementally produce results as soon as the user finishes typing/modifying a cell. Our experiments on real-life and synthetic datasets show that our proposed solution is significantly more efficient compared with applying state-of-the-art algorithms.

SkinnerDB: Regret-Bounded Query Evaluation via Reinforcement Learning

Abstract: SkinnerDB is designed from the ground up for reliable join ordering. It maintains no data statistics and uses no cost or cardinality models. Instead, it uses reinforcement learning to learn optimal join orders on the fly, during the execution of the current query. To that purpose, we divide the execution of a query into many small time slices. Different join orders are tried in different time slices. We merge result tuples generated according to different join orders until a complete result is obtained. By measuring execution progress per time slice, we identify promising join orders as execution proceeds. Along with SkinnerDB, we introduce a new quality criterion for query execution strategies. We compare expected execution cost against execution cost for an optimal join order. SkinnerDB features multiple execution strategies that are optimized for that criterion. Some of them can be executed on top of existing database systems. For maximal performance, we introduce a customized execution engine, facilitating fast join order switching via specialized multi-way join algorithms and tuple representations. We experimentally compare SkinnerDB's performance against various baselines, including MonetDB, Postgres, and adaptive processing methods. We consider various benchmarks, including the join order benchmark and TPC-H variants with user-defined functions. Overall, the overheads of reliable join ordering are negligible compared to the performance impact of the occasional, catastrophic join order choice.

Management system for processing streaming data

Abstract: Techniques are disclosed for evaluating tuples for processing by a stream application having a plurality of process elements. In one embodiment, at least one tuple to be processed by at least one processing element of the stream application is identified. A maximum duration for which the at least one processing element is allowed to process the at least one tuple is determined. A duration for which the at least one processing element is likely to process the at least one tuple is also estimated. Processing of the at least one tuple is managed based on a comparison between the maximum duration and the estimated duration.

Data Cleaning and Query Answering with Matching Dependencies and Matching Functions

Abstract: Matching dependencies were recently introduced as declarative rules for data cleaning and entity resolution. Enforcing a matching dependency on a database instance identifies the values of some attributes for two tuples, provided that the values of some other attributes are sufficiently similar. Assuming the existence of matching functions for making two attribute values equal, we formally introduce the process of cleaning an instance using matching dependencies, as a chase-like procedure. We show that matching functions naturally introduce a lattice structure on attribute domains, and a partial order of semantic domination between instances. Using the latter, we define the semantics of clean query answering in terms of certain/possible answers as the greatest lower bound/least upper bound of all possible answers obtained from the clean instances. We show that clean query answering is intractable in general. Then we study queries that behave monotonically w.r.t. semantic domination order, and show that we can provide an under/over approximation for clean answers to monotone queries. Moreover, non-monotone positive queries can be relaxed into monotone queries.

Browsing knowledge on the basis of semantic relations

Abstract: Computer-readable media and computer systems for conducting semantic processes to facilitate navigation of search results that include sets of tuples representing facts associated with content of documents in response to queries for information. Content of documents is accessed and semantic structures are derived by distilling linguistic representations from the content. Groups of two or more related words, called tuples, are extracted from the documents or the semantic structures. Tuples can be stored at a tuple index. Representations of the relational tuples are displayed in addition to documents retrieved in response to a query.