网页Query processing denotes the compilation and execution of a query specification usually expressed in a declarative database query language such as the structured query language (SQL). Query processing consists of a compile-time phase and a

Contact网页2015年3月10日The query Q1 is a simple aggregate query which computes the number of animals having high body temperatures. Q2 is a query to obtain the maximum weight

Contact网页Aggregate Query. An aggregate query is a method of deriving group and subgroup data by analysis of a set of individual data entries. The term is frequently used by database

Contact网页Definition 2. (Aggregate Functions) Aggregate Functions (AF) are applied to the returned result-set and mapping a set of returned values to a scalar resulty∈R. An AF can be

Contact网页Aggregation and query processing From the perspective of query processing (QP), aggregation can be both a costly operation, and an operation whose placement has an

Contact网页Two key parameters for query processing over continuous data-streams are (1) the amount of memory made available to the on-line algorithm, and (2) the per-item

Contact网页2021年9月15日See also. An aggregation operation computes a single value from a collection of values. An example of an aggregation operation is calculating the average

Contact网页a fee and/or special permission from the Endowment. Proceedings of the Zlst VLDB Conference Zurich, Swizerland, 1995 Stanford University aggregated. Because the

Contact网页Query processing refers to the process to answer a query to a database or an information system, which usually involves interpreting the query, searching through the space

Contact网页2015年3月10日Definition 1. When the sensing area of a sensor node s i overlaps with that of another sensor node s j, we say s i overlaps with s j. However, most of the spatio-temporal aggregate query processing techniques utilize index structures such as MVSB-tree [32], MR-tree

Contact网页Definition Query processing in a database context is the process that deduces information that is available in the database. Due to the huge amount of data available, one of the main issues of query processing is how to process queries efficiently.

Contact网页has pioneered many novel techniques for Approximate Query Processing (AQP) that could give approximate results in a fraction of time needed for computing exact results. In this work, we explore the usage of deep learning (DL) for answering aggregate queries speciﬁcally for interactive applications such as data exploration and visualization.

Contact网页2018年7月19日Abstract Incomplete data has been a longstanding issue in database community, and yet the subject is poorly handled by both theory and practice. In this , we propose to directly estimate the aggregate query result on incomplete data, rather than imputing the missing values.

Contact网页2020年5月27日Executing aggregate queries on the web of data allows to compute useful statistics ranging from the number of properties per class in a dataset to the average life of famous scientists per country.

Contact网页We introduce a first-order language with real polynomial arithmetic and aggregation operators (count, iterated sum and multiply), which is well suited for the definition of aggregate queries involving complex statistical functions. It offers a good trade-off between expressive power and complexity, with a tractable data complexity.

Contact网页2008年3月1日In query processing over spatial networks, the spatial coherency that exists in accessing data leads to a temporal coherency, that is, connected points are accessed almost concurrently. Taking this fact into consideration, it seems reasonable to place the data associated with connected points in the same disk pages so that the data

Contact网页2022年6月30日Aggregate Function: A mathematical computation involving a set of values rather than a single value. Aggregate functions are often used in databases and spreadsheets, and include the mean or sum

Contact网页Query processing in RDF stores leverages from the research and development in the field of RDBMS. All non-native RDF engines directly benefit from RDBMS query processing facilities. • Due to the absence of standards for NoSQL systems, non-native RDF systems using one of these approaches have an entry effort to provide.

Contact网页2008年3月1日 In the literature, for efficient query processing in road networks, extensive studies have been carried out on indexing [12], [14]- [16], [27] and data allocation schemes [10], [18], [25]....

Contact网页2015年3月10日Aggregate Queries: We assume that each object carries a unique identifier (e.g., an animal equipped with a “ collar ” [14] ). Specifically, in this , we consider an aggregate query Q with the following SQL syntax: Q: SELECT AGG ( a k) FROM ( SELECT AGG 1 ( S. attr 1) AS a 1,,AGG m ( S. attr m) AS a m FROM

Contact网页has pioneered many novel techniques for Approximate Query Processing (AQP) that could give approximate results in a fraction of time needed for computing exact results. In this work, we explore the usage of deep learning (DL) for answering aggregate queries speciﬁcally for interactive applications such as data exploration and visualization.

Contact网页2017年9月18日Definition Query processing in a database context is the process that deduces information that is available in the database. Due to the huge amount of data available, one of the main issues of query processing is how to process queries efficiently.

Contact网页2018年7月19日Abstract Incomplete data has been a longstanding issue in database community, and yet the subject is poorly handled by both theory and practice. In this , we propose to directly estimate the aggregate query result on incomplete data, rather than imputing the missing values.

Contact网页2008年3月1日In query processing over spatial networks, the spatial coherency that exists in accessing data leads to a temporal coherency, that is, connected points are accessed almost concurrently. Taking this fact into consideration, it seems reasonable to place the data associated with connected points in the same disk pages so that the data

Contact网页An SQL aggregate function calculates on a set of values and returns a single value. For example, the average function ( AVG) takes a list of values and returns the average. Because an aggregate function operates on a set of values, it is often used with the GROUP BY clause of the SELECT statement.

Contact网页1999年5月1日Materialized views can provide massive improvements in query processing time, of the aggregate data model ADAMO for a more user-friendly definition and query of aggregate data; (3)

Contact网页2020年11月4日non-join aggregate query as depicted in Query 1, for Big Data q ueries. Here, aggregate() denotes the aggregate function such as: Sum, Average, Variance, Standard Deviation et c. Additionally

Contact网页2007年12月1日Aggregate Query Processing for Semantic Web Databases: an The concepts and definitions of closed semirings and the aggregating relational operators provide a mathematical framework for the

Contact网页2022年6月30日An aggregate function is a mathematical computation involving a range of values that results in just a single value expressing the significance of the accumulated data it is derived from....

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