You hint at a solution already: Digest::MD5 or Digest::SHA1. 

use Digest::SHA1 'sha1_hex';

my $unique_string = 'blahblahblah';
my $sha1 = sha1_hex( $unique_string );
my $out = substr $sha1, 0, 12;

[download]

In reply to Re: Question: Generate unique/random 12-digit keys for 25,000K records, howto?? by kyle
in thread Question: Generate unique/random 12-digit keys for 25,000K records, howto?? by lihao

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