Quick References
ADO
ASP
CSS2
HTML
JavaScript
Jet SQL
VBScript
WML
WMLScript
WSH
XHTML
XML DOM
XSLT
Features
Knowledge Base
Tutorials
Partners
ZVON.ORG
XML
Planet Source Code
VisualBuilder
Web Design
Your HTML Source
XML/XSLT Forums
ASPAlliance
Scripts
Programmers Heaven
Tek-Tips Forums
Developer Fusion
Code Project
All Clauses
DELETE Statement
SELECT Statement
UPDATE Statement
CLAUSE: WHERE
DELETE [table | *] FROM table WHERE selectcriteria
SELECT table | * FROM table WHERE selectcriteria
UPDATE table SET newvalue WHERE selectcriteria
The
WHERE
clause is used with the
DELETE
,
SELECT
, and
UPDATE
statements to specify a selection criteria.
However, the
WHERE
clause is optional. Consider the following
SELECT
example which does not use a
WHERE
. This simple query will return all rows from the table SongWriters:
SELECT * FROM SongWriters;
The addition of a
WHERE
to the previous example allows you to efficiently narrow the values that will be selected. In this example, we narrow the criteria to only 'Jazz':
SELECT * FROM SongWriters WHERE MusicType='Jazz';
By using the
AND
logical operator we can further narrow the criteria:
SELECT * FROM SongWriters WHERE MusicType='Jazz' AND YearWritten=1940;
You can also use the
OR
logical operator:
SELECT * FROM SongWriters WHERE MusicType='Jazz' OR MusicType='Blues';
Within a
WHERE
clause, you can link up to a total of forty (40) expressions using logicical operators:
SELECT * FROM SongWriters WHERE MusicType='Jazz' OR MusicType='Blues' OR MusicType='Gospel' AND YearWritten>1939 AND YearWritten<1946
;
Copyright 1999-2005 by Infinite Software Solutions, Inc. All rights reserved.
Trademark Information
