%hash; # It stores about 70,000 records,just like $hash{"ID"} = "2002",etc; 

##</code><code>##

my $dbh=DBI->connect("xxxx"); # My DB is SQLSERVER 2005
foreach (keys %hash) {
	my $query = "UPDATE tab SET d='$hash{$_}' WHERE id=$_";
	die "Error $query\n" unless $dbh->do($query);
}
$dbh->disconnect;

##</code><code>##

my $dbh=DBI->connect("xxxx"); # My DB is SQLSERVER 2005
my $sth=$dbh->prepare(qq{	UPDATE tab SET d='?' WHERE id=?});
foreach (keys %hash) {
	$sth->execute($hash{$_},$_);
}
$sth->finish;
$dbh->disconnect;