Exactly. Your snippet is equivalent to:

my %h = ();
foreach (0..$#FIELDS) {
   $h{$FIELDS[$_]} = $row[$_]
}
$result = \%h;
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It's called a hash slice, and it should be documented in perldata.

(FX: perldoc perldata). Aha! I have achieved a limited form of enlightenment. Thank you for endulging my laziness ;)

ikegami explained that this uses a hash slice. He also showed an equivalent snippet that has the same effect as yours. But I'd like to show an equivalent snippet that might help you understand how the hash slice is doing its job:

my %h = ();

# @h{@FIELDS} = @row;

($h{$FIELDS[0]}, $h{$FIELDS[1]}, $h{$FIELDS[2]}, ...) =
(      $row[0] ,       $row[1] ,       $row[2] , ...);

$result = \%h;
[download]

As you can see, a hash slice is simply a convenient syntax for doing something that is not altogether very complicated. Hopefully this helps you understand it.

We don't know that he's necessarily using DBI, and, moreover, The OP was asking for explanation of a snippet he didn't understand. He wasn't asking for advice on how to refactor the code.

Update: Sorry for not reading the whole post. I still think the OP was simply asking for help understanding a snippet of code, and the context wasn't as important, but I should have read the question all the way.

We don't know that he's necessarily using DBI,

We do. He explicitely stated that @rows comes from DBI::fetchrow_array().

He wasn't asking for advice on how to refactor the code.

Maybe not, but the OP's question was answered, and it's tradition to offer alternatives, especially when they are better.