In Perl binary files don't like me.

Nor do databases, as far as I can see... :)

Since you are not asking anything specific, let me point out a few things that you should focus on:

• First, your connection code.

  my $dsn          = 'NULL';
  my $db_user_name = 'NULL';
  my $db_password  = 'NULL';
  
  my $dbh = DBI->connect($dsn, $db_user_name, $db_password) || die $dbh-
  +>errstr;
  [download]

  This code can't possibly work. I can accept that you are using fake parameters for presentation's sake, but 'NULL' is not something you can safely pass to a DBI connection method. But even assuming that your connection syntax is accepted by any driver, (not by MySQL, which you say you're using), your $dbh can't return an error string in case of failure. If connect fails, then $dbh is undefined. You must get the error string from $DBI::errstr.

• You are using this construct several times:

    $query->execute() || die $dbh->errstr;
  
      while( $a  = $query->fetchrow_array() )
      {      
          push( @results, $a );
      }
      return @results;
  [download]

  Why not using fetchall_arrayref instead?

  my $records = $query->fetchall_arrayref;
  return @$records;
  [download]

  See DBI Recipes for more examples (and for something useful for the next item as well.)

• Also, several times you are using

  WHERE ID = \'$_[0]\'
  [download]

  Code like this is subject to SQL injection. It can be also the source of some hard-to-catch mistakes. Let me chant one of the Monastery mantras: "Use Placeholders!"

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