I am surprised nobody ever mentioned

 
  $rc  = $dbh->begin_work;
  $rc  = $dbh->commit;
[download]

http://search.cpan.org/~timb/DBI-1.636/DBI.pm#commit

Any time you work with more than a tiny few records you want to use begin_work and commit

yea i know its old, and you probably know this by now