use CGI::Cookie;
my %cookies = fetch CGI::Cookie;
 my @userinfo;

if(check_login() && not validate_login() )
{
  logout_user();
} else {
  my $sth = $db->prepare("SELECT * FROM sites WHERE webmaster_email='" . $cookies{'email'} . "' AND webmaster_url='" . $cookies{'url'} . "' LIMIT 1");
  $sth->execute() or die "Can't execute statement: $DBI::errstr";  
  $userinfo = $sth->fetchrow_hashref;


  print $userinfo->{'domain'}; # für das Feld domain in der Datenbank
}

use CGI::Cookie;
my %cookies = fetch CGI::Cookie;

if(check_login() && not validate_login() )
{
   logout_user();
} else {
   my $sth = $db->prepare("SELECT * FROM sites WHERE webmaster_email='" . $cookies{'email'} . "' AND webmaster_url='" . $cookies{'url'} . "' LIMIT 1");
   $sth->execute() or die "Can't execute statement: $DBI::errstr";
   
   my @userinfos;
   while (my $ref = $sth->fetchrow_arrayref()) {
     push(@userinfos , [@$ref]);
   }
}

   my $sth = $db->prepare("SELECT * FROM sites WHERE webmaster_email= ? AND webmaster_url= ? LIMIT 1");
   $sth->execute($cookies{email}, $cookies{url}) or die "Can't execute statement: $DBI::errstr";

#!/usr/bin/perl
use CGI::Carp qw(fatalsToBrowser);

print " <input size=38 type=text name=domain disabled value='http://'.$userinfo{domain};>&nbsp;</font> ";

'http://'.$userinfo{domain};

print ' <input size=38 type=text name=domain disabled value=\'http://\'' . $userinfo->{'domain'} . '>&nbsp;</font> ';

Software error:
Can't execute statement: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'siteid FROM sites WHERE webmaster_email='counti_email=info@test.de; pat' at line 1 at spider.pl line 12.

use CGI::Carp qw(fatalsToBrowser);
use CGI::Cookie;
use DBI;

my $db = DBI->connect( 'dbi:mysql:usr_web41_1', 'web41', 'xxxxxx') ||
     die "Kann keine Verbindung zum MySQL-Server aufbauen: $DBI::errstr\n";

my %cookies = fetch CGI::Cookie;

my $sth = $db->prepare("SELECT * siteid FROM sites WHERE webmaster_email='" . $cookies{'email'} . "' AND domain='" . $cookies{'domain'} . "' LIMIT 1");
   $sth->execute() or die "Can't execute statement: $DBI::errstr";
  
  my @userinfo;
  while (my $ref = $sth->fetchrow_arrayref()) {
    push(@userinfo , [@$ref]);
  }

use CGI;
print 'URL: ', CGI::textfield( 'url', $userinfo{'domain'} ), 
  CGI::br(), 
  'E-Mail: ', CGI::textfield( 'email', $userinfo{'webmaster_email'} );

use CGI;
print 'URL: ', CGI::textfield( 'url', $userinfo{'domain'} ), 
  CGI::br(), 
  'E-Mail: ', CGI::textfield( 'email', $userinfo{'webmaster_email'} );

use CGI::Cookie;
my %cookies = fetch CGI::Cookie;
my @userinfo;

if(check_login() && not validate_login() )
{
 logout_user();
} else {
 my $sth = $db->prepare("SELECT * FROM sites WHERE webmaster_email=? AND webmaster_url=? LIMIT 1");
 $sth->execute($cookies{'email'}, $cookies{'url'} ) or die "Can't execute statement: $DBI::errstr";  
 $userinfo = $sth->fetchrow_hashref;
}

#...
# später:
use CGI;
print 'URL: ', CGI::textfield( 'url', $userinfo->{'domain'} ), 
 CGI::br(), 
 'E-Mail: ', CGI::textfield( 'email', $userinfo->{'webmaster_email'} );