does mysql alert about all the duplicates?

hi everybody

just another beginner's question.
if I insert into table and there are duplicate primary keys 
- does mysql alert about all the duplicates or just the 
first one and then exits/abandon the rest of the insert 
without any alerts for potential further duplicates?
And is this a user/config controlled behavior?

many thanks.
L.

-- 
MySQL General Mailing List
For list archives: http://lists.mysql.com/mysql
To unsubscribe:    http://lists.mysql.com/mysql