use strict;
use warnings;
...
sub write_status($$$$) {
  my $dbh = DBI->connect("DBI:mysql:mysql_socket=" ..... );
  ...
  my $result = $dbh->begin_work();
  ...
  $result = $dbh->do("UPDATE results ....");
  ...
  $result = $dbh->commit();
}
sub check_apps($\@) {
  my $dbh = DBI->connect("DBI:mysql:mysql_socket=" ..... );
  ...
  my $sth = $dbh->prepare("SELECT * FROM ....");
  ...
  if (! defined $sth->execute()) { ... }
  ...
  write_status($host, $app, $status, $version);
}

my $dbh = DBI->connect("DBI:mysql:mysql_socket=" ..... );
...
my $sth = $dbh->prepare("SELECT * FROM ....");
...
...
check_apps($host, @processes);