#!/usr/bin/perl

use strict;
use warnings;
use DBI;

my $dbh = DBI->connect(...) or die $DBI::errstr;
my $select = q~SELECT boot FROM infos~;
my $sth = $dbh->prepare($select) or die $dbh->errstr();
$sth->execute();

my ($bin) = $sth->fetchrow_array();

my $target = '/path/to/target.file';
open(my $fh,'>',$target) or die $!;
binmode $fh;
print $fh $bin;
close $fh or die $!;