Ok, in a nutshell, I'm trying to convert this: 

my $hash_ref;
while ( my $row = $sth->fetchrow_hashref ) {
  push @{ $hash_ref->{ $row->{ 'msgid' } } }, 
    { 'option'      => $row->{ 'option' }, 
      'option_data' => $row->{ 'option_data' } };
}

[download]
(which works exactly as I want)

To this: 

my $rows = $sth->fetchall_arrayref;
my %hash = map { 
  $_->[0] => { 
    'option'        => $_->[1], 
    'option_data'   => $_->[2]
  };
} @{$rows};

[download]
(which doesn't work, but iterates everything in < 10 seconds as opposed to the other way which is around 150 seconds to iterate all the rows.)

The details...
I'm trying to take a table that looks like this:
idoptionoption_data
1234foofooval
1235barbarval
1236bazbazval
1234quuxquuxval
Notice the repeated 1234, with different option and option_data.

So, like the results of the while loop, I'd like the map to end up with this: 

'1234' => [
  {
    'option_data' => 'fooval',
    'option' => 'foo'
  },
  {
    'option_data' => 'quuxval',
    'option' => 'quux'
  }
],
'1235' => [
  {
    'option_data' => 'barval',
    'option' => 'bar'
  }
],
'1236' => [
  {
    'option_data' => 'bazval',
    'option' => 'baz'
  }
]

[download]

--
"A long habit of not thinking a thing wrong, gives it a superficial appearance of being right." -- Thomas Paine
naChoZ

In reply to while/push to map, data structure confusion by naChoZ

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