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{{Short description|Database stored query result set}}
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In a [[database]], a '''view''' is the [[result set]] of a ''stored'' [[Query language|query]], which can be queried in the same manner as a persistent database collection object.<ref name="mysql-views">{{cite web |url=https://dev.mysql.com/doc/refman/8.0/en/views.html | title=25.5 Using Views | author=<!--Not stated--> | date=2023-12-12 | website=MySQL | publisher=Oracle | access-date=2023-12-12 | quote=Views are stored queries that when invoked produce a result set. A view acts as a virtual table.| archive-url=http://web.archive.org/web/20231123070115/http://dev.mysql.com:80/doc/refman/8.0/en/views.html | archive-date=2023-11-23 | url-status=live }}</ref> This pre-established query command is kept in the [[data dictionary]]. Unlike ordinary ''[[base table]]s'' in a [[relational database]], a view does not form part of the [[database design|physical schema]]: as a result set, it is a virtual table<ref name="mysql-views" /> computed or collated dynamically from data in the database when access to that view is requested. Changes applied to the data in a relevant ''underlying table'' are reflected in the data shown in subsequent invocations of the view.
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| ___location = <!-- not stated -->
| publisher = Osborne/McGraw-Hill
| pages =
| isbn = 0072118458
}}</ref>
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==Materialized views==
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Various [[database management system]]s have extended the views from read-only subsets of [[data]], particularly [[materialized view]]s: pre-executed, non-virtual views commonly used in [[Data warehouse|data warehousing]]. They give a static snapshot of the data and may include data from remote sources. The accuracy of a materialized view depends on the frequency of trigger mechanisms behind its updates.
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{{Databases}}
==References==
{{Reflist}}
{{DEFAULTSORT:View (Database)}}
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