Alright, a lot of people probably get this a lot with mySQL. Here’s the fact, there is a 99.999% chance your code is wrong and there is not a bug with mySQL.
The solution to this problem is actually really easy to figure out, it’s just that SQL has a horrible debuging scripts which make it a pain to figure out.
Just type:
Show innoDB status;
Read under the section: Latest Foreign Key Error, and there you go! Your problem explained! Just read it two or three times if you don’t get it. Trust me it helps a lot.
Happy coding
Thomas' Developer Blog 
Thank you very much this helped me alot
Comment by Luiz — November 26, 2009 @ 4:56 pm
Thanks ,
It helped me in solving my problem.
Comment by Bharathi — July 19, 2010 @ 6:09 am
Thank’s !
Comment by Matti — September 9, 2010 @ 6:10 pm
great! thx!
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