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Information retrieval (IR) in computing and information science is the task of identifying and retrieving information system resources that are relevant to an information need. The information need can be specified in the form of a search query. In the case of document retrieval, queries can be based on full-text or other content-based indexing.
A query plan (or query execution plan) is a sequence of steps used to access data in a SQL relational database management system. This is a specific case of the relational model concept of access plans. Since SQL is declarative, there are typically many
The principle is used in query processing and data intensive applications. For example, in Jack A. Orenstein's 1986 SIGMOD paper, “Spatial Query Processing in an Object-Oriented Database System,” [14] proposed concepts related to FRP as the study explores efficient methods for spatial query processing within databases. Further formalization ...
In information technology, Command Query Responsibility Segregation (CQRS) is a system architecture that extends the idea behind command–query separation (CQS) to the level of services. [1] [2] Such a system will have separate interfaces to send queries and to send commands. As in CQS, fulfilling a query request will only retrieve data and ...
The purpose of query optimization, which is an automated process, is to find the way to process a given query in minimum time. The large possible variance in time justifies performing query optimization, though finding the exact optimal query plan, among all possibilities, is typically very complex, time-consuming by itself, may be too costly ...
A systems development life cycle is composed of distinct work phases that are used by systems engineers and systems developers to deliver information systems.Like anything that is manufactured on an assembly line, an SDLC aims to produce high-quality systems that meet or exceed expectations, based on requirements, by delivering systems within scheduled time frames and cost estimates. [3]
Each system had its own concept about how a query should be structured, which would today be known as a query language. Much of the criticism of the first experiments focused on whether the experiments were truly testing the systems, or the user's ability to translate the query into the query language.
There are, for example, approaches that use timestamps or time intervals for system-wide windows or buffer-based windows for each single processing step. Sliding-window query processing is also suitable to being implemented in parallel processors by exploiting parallelism between different windows and/or within each window extent. [1]