my $sql = "Insert into tableone values('1', '2', '3')";
my $nextsql = "Insert into tabletwo values('4', '5', '6')";
my $lastsql = "Insert into tablethree values('7', '8', '9')";

my $loadHandle = $dbh->prepare("$sql; $nextsql; $lastsql;");
  
$loadHandle->execute or
  die "Could not execute SQL statement ... maybe invalid?";
....

##</code><code>##

my $sql = <<EO_SQL;
 insert into tableone values('1', '2', '3')
 insert into tabletwo values('4', '5', '6')
 insert into tablethree values('7', '8', '9')
EOF_SQL

my $loadHandle = $dbh->prepare($sql);
  
$loadHandle->execute or
  die "Could not execute SQL statement $sql ... maybe invalid?";
....