if (my $ref = $dbh->selectcol_arrayref($query)) {
  $param{welcome} = pop @$ref;
}
elsif ($DBI::err) {
  die $dbh->errstr;
}
else {
   # nothing returned, but no error?
}
[download]

update: you did notice that selectcol_arrayref returns ALL values in that column, right? I ask because using it to just get the very first row's value will get extremely inefficient fast.