The following code is providing inconsistent output. After the code is some output from runs: the first run with 200 records yields what I expect; the second, with 250 records, yields something I cant explain. Is it not permitted to change the value of a tied hash in an each iteration? 

use strict;
print "$^V\n";
my $records=shift;
unlink "test_tie_hash";
use BerkeleyDB;
my %MAIN;
tie %MAIN, "BerkeleyDB::Hash", -Filename => "test_tie_hash", -Flags =>
+ DB_CREATE, or die "Cannot open file: $! $BerkeleyDB::Error\n";
my $key="AAAAAAA";
my $store="LLLL";
foreach (1 .. $records){
    ++$key;
    $MAIN{$key}= $store;
}
untie %MAIN;

tie %MAIN, "BerkeleyDB::Hash", -Filename => "test_tie_hash", -Flags =>
+ DB_CREATE;
my %count=();
while ((my $key,my $value)=each (%MAIN)){
    $count{$value}++;
}
untie(%MAIN);
foreach(keys(%count)){
    print "INITIAL LOAD\n$_ $count{$_} records\n\n";
}
%count=();
$key="";
tie %MAIN, "BerkeleyDB::Hash", -Filename => "test_tie_hash", -Flags =>
+ DB_CREATE;
while ((my $key,my $value)=each (%MAIN)){
    if($key=~m/U/){
        $value .= "-YYYYYYYYYYYYYYYYYYYYYYYYYYYY";
        $MAIN{$key}=$value
    }
    elsif($key=~m/L/){
        $value .= "-ZZZZZZ";
        $MAIN{$key}=$value;
    }
    else{
        $value .= "-WWWWWWWWWWWWWWWWW";
        $MAIN{$key}=$value;
    }
}
untie(%MAIN);

tie %MAIN, "BerkeleyDB::Hash", -Filename => "test_tie_hash", -Flags =>
+ DB_CREATE;
while((my $key,my $value)=each (%MAIN)){
#print "$key $value\n";
$count{$value}++;
}
untie(%MAIN);
foreach(keys(%count)){
print "$_ $count{$_}\n";
}

[download]

OUTPUT 

$ perl -w test_each_tie 200
v5.10.0
INITIAL LOAD
LLLL 200 records

LLLL-WWWWWWWWWWWWWWWWW 185
LLLL-YYYYYYYYYYYYYYYYYYYYYYYYYYYY 7
LLLL-ZZZZZZ 8

[download]

$ perl -w test_each_tie 250
v5.10.0
INITIAL LOAD
LLLL 250 records

LLLL-WWWWWWWWWWWWWWWWW 101
LLLL-YYYYYYYYYYYYYYYYYYYYYYYYYYYY-YYYYYYYYYYYYYYYYYYYYYYYYYYYY 5
LLLL-ZZZZZZ-ZZZZZZ 6
LLLL-YYYYYYYYYYYYYYYYYYYYYYYYYYYY 4
LLLL-WWWWWWWWWWWWWWWWW-WWWWWWWWWWWWWWWWW 114
LLLL 16
LLLL-ZZZZZZ 4

[download]

It seems that some values in the tied hash are unaltered and some are altered more than once. Thanks.

In reply to altering value in tied hash by rlmoe

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