______crazyinsomniac_____________________________ Of all the things I've lost, I miss my mind the most. perl -e "$q=$_;map({chr unpack qq;H*;,$_}split(q;;,q*H*));print;$q/$q;"

BTREE is faster too, according to a benchmark posted here a while back.

Thanks but my question is not to get the data in the sorted order but the order in which the data was inserted.For exam if I did 323|Val and 121|Val, I would like to get 323 first.Sorry if I confused.Is there any way to achieve this using BTREE,please advise

Here is some code that would let you store things in-order. This hides the key revisions using filter_store_key and filter_fetch_key. The key thing here is that you can't use the hash functions but need to use OO interface instead {seq,put,get,del}. Hopefully you can get by with that. BerkeleyDB may have a nicer interface for what you need I'm not sure.

#!/usr/bin/perl -w
use strict;

use DB_File;
my %myhash;
my $keycount = 0; # if you're going to go away and come back
# from this program - make keycount persistent data somehow
# simple interface
my $filename = undef; # leave it undef for in-memory BDB
my $b = new DB_File::BTREEINFO;
$b->{'compare'} = \&_compare;
my $db = tie(%myhash, 'DB_File', $filename, O_CREAT|O_RDWR, 0666, $b);

$db->filter_store_key(sub { $_ .= "-".$keycount++;} );
$db->filter_fetch_key(sub { $_ =~ s/\-(\d+)$//; $_; } );
my ($key);
$key = 'first';
$db->put($key,10);
$key = 'second';
$db->put($key,12);
$key = 'third';
$db->put($key,8.0);
$key = 'fourth';
$db->put($key,'#five');
$key = undef;
my ($val,$status);
for( $status = $db->seq($key, $val, R_FIRST);
     $status == 0 ;
     $status = $db->seq($key,$val,R_NEXT) ) {
    print "$key -> $val\n";
}

sub _compare {
    my ($key,$key2) = @_;
    my $rc;
     # a little bit of protection here in case
     # something wacky happens you don't get hit
     # with undef errors out the wazzo.
    if( (my ($orderpart1) = ($key =~ /\-(\d+)/)) &&
    (my ($orderpart2) = ($key2 =~ /\-(\d+)/) )) {
    $rc = $orderpart1 <=> $orderpart2;
    } else { 
    $rc = $key cmp $key2;
    }
    $rc;
}
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