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( [id://3333]=superdoc: print w/replies, xml ) Need Help??
What is the definition of your sub _compare?
(incomplete code cannot possibly demonstrate the problem)

Use the find_dup method to see if there are any duplicates.
(change the format of your values to help you out here, or just forget the whole R_DUP thing, and do something with the keys like some_key_part_1, some_key_part_2 ...)

Here is an example adapted from the DB_File documentation to show you a neat little trick

use strict ; use DB_File ; use vars qw( $x %h ) ; # Enable duplicate records $DB_BTREE->{'flags'} = R_DUP ; $x = tie %h, "DB_File", undef, O_RDWR|O_CREAT, 0640, $DB_BTREE or die "Cannot open $filename: $!\n"; $h{'Wall'} = 'only once'; $h{'Smith'} = 'more than once'; $h{'Smith'} = 'more than twice'; $h{'Smith'} = 'three times'; my $cnt = $x->get_dup("Wall") ; print "Wall occurred $cnt times\n" ; my %hash = $x->get_dup("Wall", 1) ; print "Larry is there\n" if $hash{'Larry'} ; print "There are $hash{'Brick'} Brick Walls\n" ; my @list = sort $x->get_dup("Wall") ; print "Wall => [@list]\n" ; @list = $x->get_dup("Smith") ; print "Smith => [@list]\n" ; @list = $x->get_dup("Dog") ; print "Dog => [@list]\n" ;
particularly interesting is this tidbit
$count = $x->get_dup($key) ; @list = $x->get_dup($key) ; %list = $x->get_dup($key, 1) ;

 

Look ma', I'm on CPAN.


** The Third rule of perl club is a statement of fact: pod is sexy.

In reply to (podmaster) Re: In order traversal of BTREE keys where not all keys have duplicate values (using DB_File) by PodMaster
in thread In order traversal of BTREE keys where not all keys have duplicate values (using DB_File) by stajich

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