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Where (SQL)
{{Refimprove|date=September 2014}}
A <code>WHERE</code> clause in [[SQL]] specifies that a SQL [[Data manipulation language|Data Manipulation Language (DML)]] statement should only affect [[Row (database)|rows]] that meet specified criteria. The criteria are expressed in the form of predicates. <code>WHERE</code> clauses are not mandatory clauses of SQL DML statements, but can be used to limit the number of rows affected by a SQL DML statement or returned by a query. In brief SQL WHERE clause is used to extract only those results from a SQL statement, such as: <code>SELECT</code>, <code>INSERT</code>, <code>UPDATE</code>, or <code>DELETE</code> statement.<ref>{{cite web|url=http://www.programmingunit.com/2014/01/30/sql-clause-things-beginners-must-know/|title=SQL WHERE Clause – Things beginners must know}}</ref>

==<ref>{{Cite journal|last=Mahapatra|first=Piyush|last2=Leong|first2=Edmund|date=2014-03|title=Should We All Join the YouTube Generation?|url=http://dx.doi.org/10.1016/j.jsurg.2013.07.004|journal=Journal of Surgical Education|volume=71|issue=2|pages=162|doi=10.1016/j.jsurg.2013.07.004|issn=1931-7204}}</ref>Overview==
<code>WHERE</code> is an [[SQL:2003|SQL]] reserved word.

The <code>WHERE</code> clause is used in conjunction with SQL DML statements, and takes the following general form:

<syntaxhighlight lang="sql">
SQL-DML-Statement
FROM table_name 
(contracted; show full)<references />

== External links ==
* [http://www.psoug.org/reference/conditions.html PSOUG Home Puget Sound Oracle Users Group] gives several examples of SELECT statements with WHERE clauses.

{{SQL}}

[[Category:SQL keywords]]