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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 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 t(contracted; show full)</source>

The following [[Delete (SQL)|<code>DELETE</code> statement]] removes only those rows from table ''mytable'' where the column ''mycol'' is either NULL or has a value that is equal to 100.
<source lang="sql">
DELETE
FROM   mytable
WHERE  mycol IS NULL OR mycol = 100
</source>
kubra anjum

== Predicates ==
Simple predicates use one of the operators <code>=</code>, <code><></code>, <code>></code>, <code>>=</code>, <code><</code>, <code><=</code>, <code>IN</code>, <code>BETWEEN</code>, <code>LIKE</code>, <code>IS NULL</code> or <code>IS NOT NULL</code>.

(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]]