which means that the hash %alt_seqindex is the one I end up doing most of my searches on. It seems that building this second hash takes a very long time
Thats because Hash::Case::Preserve does everything in memory.

Here's what I'd do (assumes your keys don't end in "_\0_key") 


package BerkeleyDB::Hash::CasePreserve;

use BerkeleyDB;
use base qw[ BerkeleyDB::Hash ];

sub FETCH { $_[0]->SUPER::FETCH( lc $_[1] ) }
sub EXISTS { $_[0]->SUPER::EXISTS( lc $_[1] ) }
sub NEXTKEY {
    my $next = "";
    do {
        $next = $_[0]->SUPER::NEXT($_[1]);
    } until
        0 < index
               $next,
               "_\0_key",
                - length "_\0_key";

    return $_[0]->SUPER::FETCH( $next ); # oRiGiNal cAsE
}

sub STORE {
    $_[0]->SUPER::STORE(
        lc($_[1])."_\0_key",
        $_[1],
    ); # oRiGiNaL cAsE

    return $_[0]->SUPER::STORE( $_[1], $_[2] );
}

[download]
This has the benefit of being self contained and memory efficient.

MJD says "you can't just make shit up and expect the computer to know what you mean, retardo!"
I run a Win32 PPM repository for perl 5.6.x and 5.8.x -- I take requests (README).
** The third rule of perl club is a statement of fact: pod is sexy.

In reply to Re: Tie one hash two ways? by PodMaster
in thread Tie one hash two ways? by MrMadScience

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