My documentation states that DB_File is limited to 4GB(2**32) bytes. Maybe you have passed that limit and the DB is imploding. Hope you have a copy with less than 4GB!

Good Luck

A single key or a single value can be 4GB. A single database can be up to 256 terabytes.

http://docs.oracle.com/cd/E17076_02/html/gsg/C/databaseLimits.html

Besides being incomplete, it doesn't compile

syntax error at - line 2, near "+ or"
Execution of - aborted due to compilation errors.
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How do I post a question effectively?/http://sscce.org/ - Short, Self Contained, Correct Example

That is probably just sloppy copy / pasting out of an editor which uses "+" as some line continuation mark.

CountZero

A program should be light and agile, its subroutines connected like a string of pearls. The spirit and intent of the program should be retained throughout. There should be neither too little or too much, neither needless loops nor useless variables, neither lack of structure nor overwhelming rigidity." - The Tao of Programming, 4.1 - Geoffrey James

Actually, it appears to be sloppy copy/pasting from Re^2: storing a large hash in a database

As already noted, that still doesn't compile, which is expected as its incomplete

It is correct, and + is because of the webpage syntax.

$DB_BTREE->{'flags'} = R_DUP ;
$x = tie %dictf, "DB_File", "f.db", O_RDWR|O_CREAT, 0666, $DB_BTREE or
+ die "Cannot open file f.db: $!\n";
 
my $number = keys %dictf;
print "$number\n";

my $number = keys %dictf;
print "$number\n";

$key = $value = 0 ;
for ($status = $x->seq($key, $value, R_FIRST) ;
$status == 0 ;
$status = $x->seq($key, $value, R_NEXT) )
{ print "$key -> $value\n"; }
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However, I made it work with :

$DB_BTREE->{'flags'} = R_DUP ;
my $file="f.db";
my $x = tie %h, "DB_File", $file, O_RDWR|O_CREAT, 0666, $DB_BTREE or d
+ie "Cannot open file $file: $!\n";
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It is correct, and + is because of the webpage syntax.

No, in here, the + isn't red, its part of the code (your copy/paste)

And, in here, the code is still incomplete.

$ perl junk
Can't locate object method "TIEHASH" via package "DB_File" at junk lin
+e 2.
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See on posting complete code.

This works

#!/usr/bin/perl --
use strict; use warnings;
use File::Temp ();
use DB_File;

Main( @ARGV );
exit( 0 );
sub Main {
    Shabba(); 
    my $temp = File::Temp->new()->filename;
    my $btnf = DB_File::BTREEINFO->new;
    $btnf ->{'flags'} = R_DUP;
    HitAndQuit( $temp, $btnf , qw[ 1 2 1 4 ] );
    HitAndQuit( $temp, $btnf , qw[ 2 6 2 8 ] );
    HitAndQuit( $temp, $btnf , qw[ b o b s ] );
    unlink $temp or die "unlink $temp: $!";
}

sub HitAndQuit {
    my( $temp, $BTREEINFO , @rest ) = @_;
#~     my $tree =
    tie my(%foo),
        'DB_File',
        $temp,
        O_RDWR|O_CREAT,
        0666,
        $BTREEINFO 
            or die "Cannot tie ($temp): $!";
    for( my $ix = 0; $ix <  @rest ; $ix+=2 ){
        $foo{ $rest[ $ix] } = $rest[ $ix+1 ];
    }
    DDUP( tied %foo );
#~     untie $tree;
}


sub DDUP {
    my ( $x ) = @_;
    for (
        my $st = $x->seq( my( $key, $value), R_FIRST ) ;
        $st == 0 ;
        $st = $x->seq( $key, $value, R_NEXT )
      )
    {
        print "{ $key }{ $value } ";
    }
    print "\n";
}


sub Shabba {
    print <<"SHABBA";
### $]
#~ \$DB_File::db_ver       $DB_File::db_ver
#~ \$DB_File::db_version   $DB_File::db_version
#~ \$DB_File::VERSION      $DB_File::VERSION
########
SHABBA
}
__END__
### 5.014001
#~ $DB_File::db_ver       5.001025
#~ $DB_File::db_version   5.1
#~ $DB_File::VERSION      1.824
########
{ 1 }{ 2 } { 1 }{ 4 }
{ 1 }{ 2 } { 1 }{ 4 } { 2 }{ 6 } { 2 }{ 8 }
{ 1 }{ 2 } { 1 }{ 4 } { 2 }{ 6 } { 2 }{ 8 } { b }{ o } { b }{ s }
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