It is completely fine to make a hash key from other strings. like: 
#!/usr/bin/perl -w
use strict;

my %hash;
$hash{'my_mother=Nice,my_brother=Great;3;45;987;'}='True';

foreach my $key (keys %hash)
{
   print "$key VALUE =$hash{$key}\n";
}
__END__
prints:
my_mother=Nice,my_brother=Great;3;45;987; VALUE =True

[download]
Update:
I would argue that this is not the best way:
my $key = join ("",$value1,$value2,$value3,$value4,$value5);
consider:
my $key ="$value1$value2$value3$value4$value5";
if say $value3 doesn't exist, then,
$key = "$value1$value2$value4$value5";
Oooops!...maybe a problem!!!

$hash{"$value1;$value2;$value3;$value4;$value5"} = 123;
is "better" (provided that ";" doesn't occur in the $values).
The reason for the ";" is so that there will always be a unique value even if one of the $value vars is ""!.

In reply to Re: can i concatenate various value to form a unique key by Marshall
in thread can i concatenate various value to form a unique key by Anonymous Monk

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