perl utf8 no utf8 utf8数据库

perl utf8 插入数据库:
[oracle@oadb sbin]$ cat insertdb.pl 
use DBI;    
use Encode;
use HTTP::Date qw(time2iso str2time time2iso time2isoz);  
use Net::SMTP;
my $a="老干妈";
#   $a=encode_utf8($a);
print length($a);
print "
";
print $a;
my $dbName = 'oadb';    
my $dbUser = 'query';    
my $dbUserPass = 'kjk7787czcb';    
my $dbh = DBI->connect("dbi:Oracle:$dbName", $dbUser, $dbUserPass) or die "can't connect to database ";  
   $dbh->do("insert into tlcb values('$a')");

[oracle@oadb sbin]$ 
[oracle@oadb sbin]$ 
[oracle@oadb sbin]$ 
[oracle@oadb sbin]$ 
[oracle@oadb sbin]$ 
[oracle@oadb sbin]$ 
[oracle@oadb sbin]$ 
[oracle@oadb sbin]$ 
[oracle@oadb sbin]$ perl insertdb.pl 
9
老干妈[oracle@oadb sbin]$ 

SQL> select dump(name),name from tlcb;

DUMP(NAME)
--------------------------------------------------------------------------------
NAME
--------------------
Typ=96 Len=20: 232,128,129,229,185,178,229,166,136,32,32,32,32,32,32,32,32,32,32
,32
老干妈



启用utf8:
[oracle@oadb sbin]$ cat insertdb.pl 
use DBI;    
use Encode;
use HTTP::Date qw(time2iso str2time time2iso time2isoz);  
use Net::SMTP;
use utf8;
my $a="老干妈";
#   $a=encode_utf8($a);
print length($a);
print "
";
print $a;
my $dbName = 'oadb';    
my $dbUser = 'query';    
my $dbUserPass = 'kjk7787czcb';    
my $dbh = DBI->connect("dbi:Oracle:$dbName", $dbUser, $dbUserPass) or die "can't connect to database ";  
   $dbh->do("insert into tlcb values('$a')");

[oracle@oadb sbin]$ perl insertdb.pl 
3
Wide character in print at insertdb.pl line 10.
老干妈[oracle@oadb sbin]$ 

Typ=96 Len=20: 232,128,129,229,185,178,229,166,136,32,32,32,32,32,32,32,32,32,32
,32
老干妈

Typ=96 Len=20: 232,128,129,229,185,178,229,166,136,32,32,32,32,32,32,32,32,32,32
,32
老干妈