Duplicate entry 'S000018' for key 'PRIMARY'

[Christoph Blank]

Hi there,

I've got a weird error, I want to insert an object with the following code:

p = Property.first_or_create(:id => params[:propertyID])

It doesn't exist before this. The code is S000018. 

And I get exceptions like Duplicate entry 'S000018' for key 'PRIMARY'

Can anyone tell me why this happens and how to prevent it?

Thanks a lot,

Christoph