Y'all are completely wrong. Read the DBI POD before spouting. fetchall_arrayref() does return an array of arrays, but fetchall_arrayref({}) returns an array of hashes.

The reason why the first code works is because the TMPL_LOOP selscene is expecting an array of hashes. When you work with it, $data->[1] is a hashref. So, what you want to do is:

Example A, rewritten:

my $data = $sth->fetchall_arrayref({});

if ($data->[0]{title} eq 'large') {
    ucase( $data->[0]{title} );
}

print "First title: '$data->[0]{title}'\n";

$template->param( selscene => $data );
[download]

A few comments, in no particular order:

• You have a function called ucase(). What does it do that uc doesn't?
• Pick a better name than $data. You might not need it now, but you will need it in 6 months.
• prepare_cached() can provide a small, but noticeable, speedup with CGI scripts under mod_registry.
• Look into using the RaiseError option in your DBI connect() statement. That way, you don't have to have the or die() after every line. You will want to wrap your entire DBI interaction in something like:

  eval {
      my $sth = $dbh->prepare_cached( ... );
      $sth->execute;
      my $stuff = $sth->festchall_arrayref({});
      $template->param( selscene => $data );
  }; if ($@) {
      # Do some error handling here.
  }
  [download]

  It's a lot easier to read and you still have all the error handling. You may want to turn PrintError off, if you do this.