dbi问题

neter

我现在想做一个注册模块，需要判断用户名是否存在，语句如下：my$dbh = DBI->;connect("DBI:mysql:zrsm","neter","123" || die DBI->;errstr;
my        $sth = $dbh->;prepare("select * from s_user where username=$username" || die DBI::errstr;
        $sth->;execute;
怎样操作$sth才能确定$username是否存在？

Perl小手

$sth->;execute || (($r=$DBI::err) &&($str=$DBI::errstr));
my @row_ary  = $sth->;fetchrow_array;
if ($row_ary[0]) {
      print "username is: $row_ary[0] \n";
}

neter

3Q