[PHP] update count

2004-06-16 Thread Bob Lockie 
What is the best way to only do an update if it going to update only one 
row?
I want to protect my code so that it won't accidentally update more than 
one row.
I can do a select first but there must be an easier way. :-)

--
PHP General Mailing List (http://www.php.net/)
To unsubscribe, visit: http://www.php.net/unsub.php

RE: [PHP] update count

2004-06-16 Thread Jay Blanchard 
[snip]
What is the best way to only do an update if it going to update only one

row?
I want to protect my code so that it won't accidentally update more than

one row.
I can do a select first but there must be an easier way. :-)
[/snip]


Do the update with conditions (this is a SQL question)

UPDATE `tblFOO` SET `bar` = 'a_value' WHERE `barID` = '227098762' 

will only update the record(s) where barID is  227098762

--
PHP General Mailing List (http://www.php.net/)
To unsubscribe, visit: http://www.php.net/unsub.php

Re: [PHP] update count

2004-06-16 Thread John Nichel 
Bob Lockie wrote:
What is the best way to only do an update if it going to update only one 
row?
I want to protect my code so that it won't accidentally update more than 
one row.
I can do a select first but there must be an easier way. :-)

UPDATE thisDB.thisTable SET thisTable.thisColumn = 'thisValue' WHERE 
thisTable.uniqueColumn = 'someUniqueValue'

--
John C. Nichel
KegWorks.com
716.856.9675
[EMAIL PROTECTED]
--
PHP General Mailing List (http://www.php.net/)
To unsubscribe, visit: http://www.php.net/unsub.php

Re: [PHP] update count

2004-06-16 Thread Robin Vickery 
On Wed, 16 Jun 2004 09:40:52 -0400, Bob Lockie [EMAIL PROTECTED] wrote:
 
 What is the best way to only do an update if it going to update only one
 row?

You don't say what database you're using.

The general way is to use a unique key in the WHERE clause.

   UPDATE tablename SET foo=1 WHERE id=123

MySQL also lets you use a LIMIT clause that will either limit the
number of rows affected by the update, or matched by the WHERE clause
depending on the MySQL version.

  UPDATE tablename SET foo=1 WHERE bar=2 LIMIT 1

  -robin

-- 
PHP General Mailing List (http://www.php.net/)
To unsubscribe, visit: http://www.php.net/unsub.php

Re: [PHP] update count

2004-06-16 Thread Bob Lockie 

What is the best way to only do an update if it going to update only one
row?

You don't say what database you're using.
The general way is to use a unique key in the WHERE clause.
   UPDATE tablename SET foo=1 WHERE id=123
MySQL also lets you use a LIMIT clause that will either limit the
number of rows affected by the update, or matched by the WHERE clause
depending on the MySQL version.
  UPDATE tablename SET foo=1 WHERE bar=2 LIMIT 1
  -robin
The LIMIT clause is perfect but is that standard SQL?
I am using MySQL right now but it will be run on another database 
eventually.

--
PHP General Mailing List (http://www.php.net/)
To unsubscribe, visit: http://www.php.net/unsub.php

Re: [PHP] update count

2004-06-16 Thread Daniel Clark 
If your table has a primary key, or auto increment field works well and is
quick.

 What is the best way to only do an update if it going to update only one
 row?
 I want to protect my code so that it won't accidentally update more than
 one row.
 I can do a select first but there must be an easier way. :-)

-- 
PHP General Mailing List (http://www.php.net/)
To unsubscribe, visit: http://www.php.net/unsub.php