Re: Get a hash object from a database with DBI for use with HTML::Template

[Cine]

A couple of comments on your code:

• You should use placeholders for values where possible for many reasons, including security, problems with quoting etc. That is you should change

      my $stmt = "SELECT * FROM $table WHERE $key_col = '$key_val'";
      my $sth = $dbhandle->prepare( $stmt );
      $sth->execute();
  

  into

      my $stmt = "SELECT * FROM $table WHERE $key_col = ?";
      my $sth = $dbhandle->prepare( $stmt );
      $sth->execute($key_val);
  

• You should errorcheck your database stuff. Add a || die $DBI::errstr to all your DBI->connect, $dbh->prepare and $sth->execute.
• You only need two row, so only get those. That is change:

      my $ref = $sth->fetchall_arrayref();
      $sth->finish();
      return map { $_->[$name_col] => $_->[$val_col] } @$ref;
  

  into

      my $ref = $sth->fetchall_hashref([$name_col,$val_col]);
      $sth->finish();
      return map {@$_} @$ref;
  

• print "Content-Type: text/html\n\n"; is wrong. The HTTP standard says it should be \r\n\r\n. However most browsers dont care ;)
• Dont use a & in a sub call without needing it. It overrides any prototype you may add at a later time to make perl check the number/type of params to get_hash.
• Dont overgeneralize. If you only use get_hash for this specific purpose, then fill in the tablename/colname and select only the two rows you need instead of *.

T I M T O W T D I

[jeffa]

"Add a || die $DBI::errstr to all ... "

Too much typing, especially after the code has already been typed. Just add {RaiseError => 1} to connect():

my $dbh = DBI->connect(
   "dbi:mysql:mydb", "user", "pass",
   {RaiseError => 1},
);

"Dont use a & in a sub call without needing it. It overrides any prototype you may add ..."

Perl prototypes really are not very good, IMHO. I prefer to avoid them, opting for good documentation instead. Check out (tye)Re: A question of style for some good info.

jeffa

L-LL-L--L-LL-L--L-LL-L--
-R--R-RR-R--R-RR-R--R-RR
B--B--B--B--B--B--B--B--
H---H---H---H---H---H---
(the triplet paradiddle with high-hat)