Altering row content

I have a table and I'd like to alter the contens of an existing row. How would I change a spasific column entry?

Use sql UPDATE like this:

<BLOCKQUOTE><font size="1" face="Verdana,Arial,Helvetica">code:</font><HR><pre>
UPDATE tablename SET columname=value WHERE ID=value
[/code]

You won't want to forget the WHERE statement with some type of unique identifier for the data or you'll update EVERY row in the table


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Adding on to TDavid's suggestion, prior to doing your update you may want to do:
<BLOCKQUOTE><font size="1" face="Verdana,Arial,Helvetica">code:</font><HR><pre>
SELECT columname FROM tablename WHERE id=value
[/code]
first. That'll give you the rows that you'll be updating when you execute the UPDATE statement (so long as the DB doesn't change between the SELECT and UPDATE). If you get more than one row back, be careful. ;-)