"you're not doing any error checking on $dbh->prepare or $dbh->do ..."

But if the OP had set RaiseError to true in the connect() method, then this would be handled transparently and automatically. :)

my $dbh = DBI->connect(
   $datasource,$user,$pass,
   {RaiseError => 1},
);
[download]

L-LL-L--L-LL-L--L-LL-L--
-R--R-RR-R--R-RR-R--R-RR
B--B--B--B--B--B--B--B--
H---H---H---H---H---H---
(the triplet paradiddle with high-hat)