http://www.mysql.com/doc/en/INSERT.html tells you the use for ON DUPLICATE KEY UPDATE, so you may want to check that out.

I'd be interested to hear more details about the situation which you are stuck in, as I'd like to see an example of where you'd want to use this feature. Myself, I use primary keys because of the fact that they normally must be unique. I have yet to come across a case where refusing to add data to the table because of an existing primary key value is a bad idea.

I hope you post more info so that I can understand your position. ON DUPLICATE KEY UPDATE acts differently depending on how the table is set up (ie: if more than one column is marked as unique). The link at the beginning of the post vaguely mentions this fact.

In reply to Re: MySQL and Duplicate Keys by Coruscate
in thread MySQL and Duplicate Keys by cidaris

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