About: Null (SQL)

Property	Value
dbo:description	special marker and keyword in SQL indicating that something has no value (en) SQL中的特殊标记和关键字 (zh) علامة خاصة وكلمة رئيسية في أس كيو إل (SQL) (ar) Schlüsselwort in SQL und Kennzeichnung für nicht vorhandene Datenwerten innerhalb einer Datenbank (de) λέξη κλειδί στην SQL (el)
dbo:thumbnail	wiki-commons:Special:FilePath/Db_null.png?width=300
dbo:wikiPageExternalLink	https://archive.org/details/databaserelation00date https://web.archive.org/web/20130412031441/http:/psoug.org/reference/null.html http://bugs.sun.com/bugdatabase/view_bug.do%3Fbug_id=4032732 http://www.psoug.org/reference/null.html http://www.thethirdmanifesto.com/ http://www09.sigmod.org/sigmod/record/issues/0809/p23.grant.pdf http://www.u.arizona.edu/~rubinson/scrawl/Rubinson.2007.Nulls_Three-Valued_Logic_and_Ambiguity_in_SQL.pdf http://ceur-ws.org/Vol-866/paper8.pdf http://www.iaeng.org/IJCS/issues_v35/issue_3/IJCS_35_3_08.pdf https://web.archive.org/web/20130405060544/http:/www.sqlexpert.co.uk/2006/05/treatment-of-nulls-by-oracle-sql.html http://www.acm.org/sigmod/record/issues/9409/sql.ps https://zenodo.org/record/1038419%7Cdoi=10.3233/978-1-60750-690-4-354%7Cyear=2011
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dbp:align	center (en)
dbp:caption	The Codd table Emp may represent the relation EmpH22 or EmpH37, as pictured. (en)
dbp:content	class="wikitable" style="display: inline-table !important" + Emp ! Name !! Age George 43 Harriet Charles 56 class="wikitable" style="display: inline-table !important" + EmpH22 ! Name !! Age George 43 Harriet 22 Charles 56 class="wikitable" style="display: inline-table !important" + EmpH37 ! Name !! Age George 43 Harriet 37 Charles 56 (en)
dbp:date	2013-04-12 (xsd:date) 2016-03-05 (xsd:date)
dbp:innerstyle	display: flex; flex-flow: row wrap; justify-content: space-evenly; (en)
dbp:url	https://web.archive.org/web/20130412031441/http:/psoug.org/reference/null.html https://web.archive.org/web/20160305071445/http:/www.u.arizona.edu/~rubinson/scrawl/Rubinson.2007.Nulls_Three-Valued_Logic_and_Ambiguity_in_SQL.pdf
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dct:subject	dbc:Articles_with_example_SQL_code dbc:SQL_keywords dbc:Unknown_content
gold:hypernym	dbr:Marker
rdfs:label	Null (SQL) (en) قيمة فارغة (إس كيو إل) (ar) Null (SQL) (el) Null (SQL) (es) Null (SQL) (ko) Null (SQL) (pl) Null (SQL) (pt) NULL (SQL) (ru) Null (SQL) (uk) 空值 (SQL) (zh)
rdfs:seeAlso	dbr:Option_type
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