It's really not an issue of the storage mechanism (dbm vs. RDBMS), just a simple problem with Perl's TIE mechanism. In your case, I would change it so that you always write to $sessions->{$session_id} when you modify anything in the session. For example: 
my $aref = $sessions->{$session_id};
$aref->{timestamp} = time;
$sessions->{$session_id} = $aref;

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In reply to Re: Re: Re: Problem storing value in persistent hash with MLDBM by perrin
in thread Problem storing value in persistent hash with MLDBM by relax99

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