SELECT bin_data FROM photos

$md5 = Digest::MD5->new;
$sum = $md5->add($bin_data)->hexdigest;

SELECT MD5(bin_data)...

#!/usr/bin/perl

$| = 1;

use strict;
use warnings;

use Digest::MD5;
use DBI;

my $data_source = 'dbi:mysql:test';
my $username = 'test';
my $password = 'test';
my $buffer;

my $dbh = DBI->connect($data_source, $username, $password) or die $DBI::errstr;

my $rv = $dbh->do(<<"SQL") or die $DBI::errstr;
CREATE TABLE 
    IF NOT EXISTS test (
    id INT,
    myData LONGBLOB,
    myName CHAR(64),
    myMd5 CHAR(128)
    );
SQL

my ($md5,$sum);
my $sth;

for my $j (1..10) {
    my $rnd = rand(time());
    my $i = $j + int($rnd);
    
    $buffer = 'XFCE#'. chr(rand(100)) . '(123a3#aA2' . "\xAA" . "\011" . '211x0|c' . chr(rand(100)) . '022' . "\xDF" . "171" .  chr(rand(100)) . "616" . $rnd;
    
    $md5 = Digest::MD5->new;
    $md5->add($buffer);
    $sum = $md5->hexdigest;
    
    $sth = $dbh->prepare(<<SQL) or die $DBI::errstr;
    INSERT INTO test ( id, myData, myName, myMd5 ) 
    VALUES ( ?, ?, ?, ?);
SQL
    $rv = $sth->execute($i, $buffer, $rnd, $sum) or die $DBI::errstr;;
}
    
$sth = $dbh->prepare(<<SQL) or die $DBI::errstr;
SELECT myData,myMd5,MD5(myData),id from test;
SQL
$rv = $sth->execute() or die $DBI::errstr;
while (my @row = $sth->fetchrow_array) {
    $buffer = $row[0];
    $md5 = Digest::MD5->new;
    $md5->add($buffer);
    $sum = $md5->hexdigest;

    print $row[3], ':  ';
    die if $row[1] ne $row[2]; # gespeicherte MD5 ungleich durch MySQL errechnete?
    die if $sum ne $row[2]; # durch Digest::MD5($buffer) errechnete MD5 ungleich durch MySQL errechnete?
    print "ok", "\n";
}

1;

SELECT bin_data FROM photos

$md5 = Digest::MD5->new;
$sum = $md5->add($bin_data)->hexdigest;

    
#<snip>
#
    my $rnd = rand(time());
    my $i = int($rnd);
     
    my $FH;
    open($FH, 'picture.png') or die $!;
    binmode($FH);
    local ($/) = undef;
    $buffer = <$FH>;
    close($FH) or die $!;
    $md5 = Digest::MD5->new;
    $md5->add($buffer);
    $sum = $md5->hexdigest;
    
    $sth = $dbh->prepare(<<SQL) or die $DBI::errstr;
INSERT INTO test 
( id, myData, myName, myMd5 ) 
VALUES ( ?, ?, ?, ?);
SQL
    $rv = $sth->execute($i, $buffer, $rnd, $sum) or die $DBI::errstr;
#<snip>