my $select = "SELECT * FROM mysqlTable"; # or whatever
my $ad_dbh    = DBI->connect(...AnyData...);
my $mysql_dbh = DBI->connect(...mysql...  );
$ad_dbh->import("tmp",'DBI',$mysql_dbh,{sql=>$select});
$ad_dbh->export("tmp",'CSV','myfile.csv);
# all done!