overwriting references in a loop

toadi has asked for the wisdom of the Perl Monks concerning the following question:

I have a hash. with is filled with key value/pairs. In this hash I have one key: a array_ref with is also filles with hash references.
So I fetch the data for these hashes and fill the array:


  my @array1;
  while( $sth->fetch ) {
    my %fetch2;
    $fetch2{username} = $username;
    $fetch2{accountid} = $accountid;
    $fetch2{statusid} = $statusid;

    print "$username - $accountid - $statusid \n";

   push (@array1, \%fetch2);

  }
  $fetch1{array_ref} = \@array1;

  return \%fetch1;
[download]

Now my question is: Can I be sure that one of the hash references can be overwritten by another one when declaring them at the start of the while??? And if so can I solve this problem in a better way???

--
My opinions may have changed,
but not the fact that I am right

Edit kudra, 2002-05-06 Changed title

Comment on overwriting references in a loop Download Code

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Re: Pushing References by tadman (Prior) on May 06, 2002 at 14:26 UTC
Before you get too sidetracked, you might want to look at the DBI call `selectall_hashref()` which returns a hash based on a key field. As to your references being overwritten, here is an example of the wrong way: `my @foo; my %bar; while ($sth->fetch()) { @bar{'name','age'} = ($name, $age); push (@foo, \%bar); }` [download] This uses the same hash each time, so your array actually contains duplicates. In your example you are declaring it specifically each time, so each `%fetch2` is unique. Summary: Declared inside means unique, outside means recycled. `s/\?+/\?/g; # BTW`	[reply] [d/l] [select]
Re: references by BUU (Prior) on May 06, 2002 at 12:27 UTC
It might make a bit more sense to just use hashkeys with in the second array.. i.e. `$array1[0]{username}=$username` etc. Also note that your pushing a refference to an array `$fetch1{array_ref} = \@array1;` [download] This is pointing to @array1 specifically, if you just wanted an annonymous array, then drop the backslash, and (if you need to) surround it with parens.	[reply] [d/l] [select]