Null (SQL) (English Wikipedia)

Hans-Joachim, K. (2003). "Null Values in Relational Databases and Sure Information Answers". Semantics in Databases. Second International Workshop Dagstuhl Castle, Germany, January 7–12, 2001. Revised Papers. Lecture Notes in Computer Science. Vol. 2582. pp. 119–138. doi:10.1007/3-540-36596-6_7. ISBN 978-3-540-00957-3. Archived from the original on 2018-07-07. Retrieved 2015-08-28.
Imieliński, T.; Lipski, W. Jr. (1984). "Incomplete information in relational databases". Journal of the ACM. 31 (4): 761–791. doi:10.1145/1634.1886. S2CID 288040.
Arenhart, Krause (2012), "Classical Logic or Non-Reflexive Logic? A case of Semantic Underdetermination", Revista Portuguesa de Filosofia, 68 (1/2): 73–86, doi:10.17990/RPF/2012_68_1_0073, JSTOR 41955624.

iso.org (Global: 629^th place; English: 610^th place)

ISO/IEC (2003). ISO/IEC 9075-1:2003, "SQL/Framework". ISO/IEC. Section 4.4.2: The null value.

jstor.org (Global: 26^th place; English: 20^th place)

Arenhart, Krause (2012), "Classical Logic or Non-Reflexive Logic? A case of Semantic Underdetermination", Revista Portuguesa de Filosofia, 68 (1/2): 73–86, doi:10.17990/RPF/2012_68_1_0073, JSTOR 41955624.

microsoft.com (Global: 153^rd place; English: 151^st place)

msdn2.microsoft.com

"Creating Unique Indexes". PostfreSQL. September 2007. Retrieved November 6, 2008.

postgresql.org (Global: low place; English: 8,344^th place)

"PostgreSQL 8.0.14 Documentation: Index Types". PostgreSQL. Retrieved 6 November 2008.
"PostgreSQL 8.0.14 Documentation: Unique Indexes". PostgreSQL. Retrieved November 6, 2008.

semanticscholar.org (Global: 11^th place; English: 8^th place)

api.semanticscholar.org

Imieliński, T.; Lipski, W. Jr. (1984). "Incomplete information in relational databases". Journal of the ACM. 31 (4): 761–791. doi:10.1145/1634.1886. S2CID 288040.

sfdama.org (Global: low place; English: low place)

Date, Chris. "Abstract: The Closed World Assumption". Data Management Association, San Francisco Bay Area Chapter. Archived from the original on 2007-05-19. Retrieved May 29, 2007.

sqlservercentral.com (Global: low place; English: low place)

Coles, Michael (June 27, 2005). "Four Rules for Nulls". SQL Server Central. Red Gate Software.
Coles, Michael (February 26, 2007). "Null Versus Null?". SQL Server Central. Red Gate Software.

thethirdmanifesto.com (Global: low place; English: low place)

Darwen, Hugh; Date, Chris. "The Third Manifesto". thethirdmanifesto.com. Retrieved May 29, 2007.

uni-kiel.de (Global: 6,155^th place; English: low place)

is.informatik.uni-kiel.de

Hans-Joachim, K. (2003). "Null Values in Relational Databases and Sure Information Answers". Semantics in Databases. Second International Workshop Dagstuhl Castle, Germany, January 7–12, 2001. Revised Papers. Lecture Notes in Computer Science. Vol. 2582. pp. 119–138. doi:10.1007/3-540-36596-6_7. ISBN 978-3-540-00957-3. Archived from the original on 2018-07-07. Retrieved 2015-08-28.

unsw.edu.au (Global: 4,584^th place; English: 3,029^th place)

cse.unsw.edu.au

Ron van der Meyden, "Logical approaches to incomplete information: a survey" in Chomicki, Jan; Saake, Gunter (Eds.) Logics for Databases and Information Systems, Kluwer Academic Publishers ISBN 978-0-7923-8129-7, p. 344; PS preprint (note: page numbering differs in preprint from the published version)

warwick.ac.uk (Global: 4,378^th place; English: 2,689^th place)

dcs.warwick.ac.uk

Darwen, Hugh. "The Askew Wall" (PDF). dcs.warwick.ac.uk. Retrieved May 29, 2007.

web.archive.org (Global: 1^st place; English: 1^st place)

Hans-Joachim, K. (2003). "Null Values in Relational Databases and Sure Information Answers". Semantics in Databases. Second International Workshop Dagstuhl Castle, Germany, January 7–12, 2001. Revised Papers. Lecture Notes in Computer Science. Vol. 2582. pp. 119–138. doi:10.1007/3-540-36596-6_7. ISBN 978-3-540-00957-3. Archived from the original on 2018-07-07. Retrieved 2015-08-28.
Date, Chris. "Abstract: The Closed World Assumption". Data Management Association, San Francisco Bay Area Chapter. Archived from the original on 2007-05-19. Retrieved May 29, 2007.

Null (SQL) (English Wikipedia)

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