Incremental update insert ... on duplicate key

Question

Is there a way to do incremental update to double duplicate key update in mysql?

W / error example:

insert into blah (user_id, prefix, email_id, field, source) 
select user_id, substring(name, 1, 3), contact_email_id, 2, source from address_book 
on duplicate key update source = source + values(source);

ERROR 1052 (23000): Column 'source' in field list is ambiguous

Answer 1

NO , you simply cannot specify source = source + values(source);
because the source table is blahnot included in the selectuse of the alias will not be fixed.

Workaround will use left join

insert into blah (user_id, prefix, email_id, field, source) 
select 
  ab1.user_id, substring(ab1.name, 1, 3), ab1.contact_email_id, 2, 
  if(ab2.source, ab1.source+ab2.source, ab1.source)
from 
  address_book ab1
left join
  blah1 as ab2
on 
  ab1.user_id=ab2.user_id
on duplicate key 
update source = values(source); 
/* values(source) = ab1.source+ab2.source if duplicate found */

beware of relationships 1:N

Answer 2

What if you prefix the table to the column name, i.e. blah.source, address_book.source?