SQL extension for spatio-temporal dataThe VLDB Journal - - 2006
Jose R. Rios Viqueira, Nikos A. Lorentzos
An SQL extension is formalized for the management of spatio-temporal data, i.e. of spatial data that evolves with respect to time. The extension is dedicated to applications such as topography, cartography, and cadastral systems, hence it considers discrete changes both in space and in time. It is based on the rigid formalization of data types and of SQL constructs. Data types are defined in terms...... hiện toàn bộ
PSoup: a system for streaming queries over streaming dataThe VLDB Journal - Tập 12 - Trang 140-156 - 2003
Sirish Chandrasekaran, Michael J. Franklin
Recent work on querying data streams has focused on systems where newly arriving data is processed and continuously streamed to the user in real time. In many emerging applications, however, ad hoc queries and/or intermittent connectivity also require the processing of data that arrives prior to query submission or during a period of disconnection. For such applications, we have developed PSoup, a...... hiện toàn bộ
ArchIS: an XML-based approach to transaction-time temporal database systemsThe VLDB Journal - - 2008
Fusheng Wang, Carlo Zaniolo, Xin Zhou
Effective support for temporal applications by database systems represents an important technical objective that is difficult to achieve since it requires an integrated solution for several problems, including (i) expressive temporal representations and data models, (ii) powerful languages for temporal queries and snapshot queries, (iii) indexing, clustering and query optimization techniques for m...... hiện toàn bộ
Fast and accurate text classification via multiple linear discriminant projectionsThe VLDB Journal - Tập 12 - Trang 170-185 - 2003
Soumen Chakrabarti, Shourya Roy, Mahesh V. Soundalgekar
Support vector machines (SVMs) have shown superb performance for text classification tasks. They are accurate, robust, and quick to apply to test instances. Their only potential drawback is their training time and memory requirement. For n training instances held in memory, the best-known SVM implementations take time proportional to na, where a is typically between 1.8 and 2.1. SVMs have been tra...... hiện toàn bộ
Comparison and evaluation of state-of-the-art LSM merge policiesThe VLDB Journal - Tập 30 - Trang 361-378 - 2021
Qizhong Mao, Steven Jacobs, Waleed Amjad, Vagelis Hristidis, Vassilis J. Tsotras, Neal E. Young
Modern NoSQL database systems use log-structured merge (LSM) storage architectures to support high write throughput. LSM architectures aggregate writes in a mutable MemTable (stored in memory), which is regularly flushed to disk, creating a new immutable file called an SSTable. Some of the SSTables are chosen to be periodically merged—replaced with a single SSTable containing their union. A merge ...... hiện toàn bộ
Dictionary-based order-preserving string compressionThe VLDB Journal - Tập 6 - Trang 26-39 - 1997
Gennady Antoshenkov
As no database exists without indexes, no index implementation exists without order-preserving key compression, in particular, without prefix and tail compression. However, despite the great potentials of making indexes smaller and faster, application of general compression methods to ordered data sets has advanced very little. This paper demonstrates that the fast dictionary-based methods can be ...... hiện toàn bộ
A survey of approaches to automatic schema matchingThe VLDB Journal - - 2001
Erhard Rahm, Philip A. Bernstein
Schema matching is a basic problem in many database application domains, such as data integration, E-business, data warehousing, and semantic query processing. In current implementations, schema matching is typically performed manually, which has significant limitations. On the other hand, previous research papers have proposed many techniques to achieve a partial automation of the match operatio...... hiện toàn bộ
Fast stochastic routing under time-varying uncertaintyThe VLDB Journal - Tập 29 - Trang 819-839 - 2019
Simon Aagaard Pedersen, Bin Yang, Christian S. Jensen
Data are increasingly available that enable detailed capture of travel costs associated with the movements of vehicles in road networks, notably travel time, and greenhouse gas emissions. In addition to varying across time, such costs are inherently uncertain, due to varying traffic volumes, weather conditions, different driving styles among drivers, etc. In this setting, we address the problem of...... hiện toàn bộ