Not that complex ;-), just do: 
use strict;

my %a;

$a{"abc"} ++;
print $a{"abc"};

[download]
Two things:
  1. In this case you don't need to initilize the hash element, as Perl will initilize it to 0 for you, in a number context.
  2. Just in case you do not know, exists is different from defined. If a hash element has value undef, than it exists, although not defined.

    This demo would help you to understand: 
    use strict;

my %a;

check();
print "now set abc to undef\n";
$a{"abc"} = undef;
check();

sub check {
    print "defined\n" if (defined($a{"abc"}));
    print "exists\n" if (exists($a{"abc"}));
}

    [download]

In reply to Re: database unclarity when finding 'unitinitaliazed' everywhere by pg
in thread database unclarity when finding 'unitinitaliazed' everywhere by sulfericacid

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