Dear monks, you may think this program a crazy one, but I think it worth to discuss.

I was trying to fetch data from two different tables into separate hashes. I always use 'strict'. I use DBI's function  bind_columns with the fancy syntax. The code is

    my $data  = {};
    my $SQL   = "SELECT * FROM my_table ORDER BY order";
    my $sth   = $dbh->prepare( $SQL );
    $sth->execute() or die DBI->errstr;

    my %row;

    $sth->bind_columns( \( @row{ @{ $sth->{ NAME_uc } } } ));
    $i = 1;
    
    while ( $sth->fetch() ){
        push @names, $row{ 'NAME' };
        delete $row{ 'NAME' };             #this line causes problem a
+t 'bind_columns' down there
        $data->{"data_$i"} = { %row };
        $i++;
    }
    $sth->finish();
    
    my $second_data  = {};
    $SQL2    = "SELECT * FROM my_second_table ORDER BY order";
    my $sth2 = $dbh->prepare( $SQL2 );
    $sth2->execute();

    my %row2    = ();

    $sth2->bind_columns( \( @row2 { @{ $sth2->{ NAME_lc } } } )); # Er
+ror due to delete $row{ 'NAME' }; at top
    $i=1;       

    while ( $sth2->fetch() ){
        
        $second_data->{"data_$i"} = { %row2 };
        $i++;

    }
    $sth2->finish();
[download]

I get the error

"Can't use an undefined value as an ARRAY reference at /myprogram.pl l
+ine 23."
[download]

The line causing error is

$sth2->bind_columns( \( @row2 { @{ $sth2->{ NAME_lc } } } ));
[download]

When I comment line delete $row{ 'NAME' }; everything works fine.

I wonder why it throws this error since first set of variables has NO connection with the second set, except that they use same DB handle.

Other Observations I have made are

• Deleting data from any other hash does NOT make any problem.
• I tried

  while ( $sth->fetch() ){
      %record=%row;
      push @names, $record{ 'NAME' };
      delete $record{ 'NAME' };
      $data->{"data_$i"} = { %record };
      $i++;
  }
  [download]

  This also failed :(
• I tried

  while ( $sth->fetch() ){
      %record=(%row);
      push @names, $record{ 'NAME' };
      delete $record{ 'NAME' };
      $data->{"data_$i"} = \%record;
      $i++;
  }
  [download]

  This also made NO difference

Thanks in advance for the help.

--VC

---

There are three sides to any argument.....
your side, my side and the right side.

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