No. Your code checks if the value under "key1" of the second hashref in the array is false.

Consider:

#!/usr/bin/perl
use strict;

my @array = 
(
    {key1=>0, key2=>2, key3=>3}, 
    {key1=>1, key2=>2, key3=>3}, 
    {key1=>0, key2=>2, key3=>3} 
);

my $amount = scalar(@array);

if (!$array[0..$amount]->{key1}) 
{
    print "no\n"
}
[download]

which should print "no" but does not, and

#!/usr/bin/perl

use strict;

my @array = 
(
    {key1=>0, key2=>2, key3=>3}, 
    {key1=>1, key2=>2, key3=>3}, 
    {key1=>0, key2=>2, key3=>3} 
);

my $amount = scalar(@array);

if (!$array[0..$amount]->{key1}) 
{
    print "no\n"
}
[download]

which should not print "no" but does.