If you're not doing it already, trap errors with ALL queries. Set the RaiseError flag on your db handle, and then make all executes look like this, or with some other useful error handling:

...
my $query_handle = $db_handle->prepare($query);
eval {
   $query_handle->execute();
};
if ( $@ ) {
   confess "Query Error $DBI::errstr\nQuery: $query\n";
}
[download]

And if you are using Bind Params, dump them too.

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