From what I've read and from my recent experience with DBI, you'll have an easier time if you bind your columns. You can do something like this: 

   my $b;
   my $sql            = qq{SELECT b FROM blah WHERE user = ?};
   my $sth            = $dbh->prepare("$sql");
      $sth           -> execute("bahbah");
      $sth           -> bind_col(1,\$b);
   while( $sth->fetchall_arrayref ) {
      print "$b\n"    if $_;
   }

[download]

Update: Indeed, runrig, that was bad. I munged the following two methods (perhaps neither of which fully applies since the OP is fetching hashrefs.) 

   my $b;
   my $sql   = qq{SELECT b FROM blah WHERE user = ?};
   my $sth   = $dbh->prepare("$sql");
      $sth  -> execute('bahbah');
      $sth  -> bind_col(1,\$b);
   while( $sth->fetch ) {
      print "$b\n";
   }
   ################
   # OR:
   ################
   my $sql   = qq{SELECT b FROM blah WHERE user = ?};
   my $sth   = $dbh->prepare("$sql");
      $sth  -> execute('bahbah');
   my $rows  = [];    # cache for batches of rows
   while(my $row = shift(@$rows) 
                || shift(@{$rows=$sth->fetchall_arrayref([0],10_000)||
+[]})) {
      print "$row->[0]\n";
   }

[download]

Incidentally, while both produce the same lists, do you know why the latter also gives "ERROR no statement executing (perhaps you need to call execute first)"?

In reply to Re: DBI and fetchall_arrayref by hbm
in thread DBI and fetchall_arrayref by Anonymous Monk

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