Thank you, I finally found the culprit, it is really DBI (mysql).

This workaround made my program working:

The beginning of my subroutine:

sub write_status($$$$) {
  my $host = $_[0];
  my $app = $_[1];
  my $status = $_[2];
  my $version = $_[3];
  my $result = $dbh->begin_work();
  if (! defined $result) { $result = -1; }
  if ($result < 0) {
    print STDERR "\n" . $0 . ": CHYBA: " . $dbh->errstr . "\n";
    return ISHN_ERR_INTERNAL;
  }

[download]
I needed to add this dummy UPDATE to somehow reset something (without it only few or none rows were updated): 
  my $statement = q{UPDATE results
                    SET status = ?, verze = 'N/A'
                    WHERE host = ? AND app = ?;};
  $result = $dbh->do($statement, undef, $status, $host, $app);
  if (! defined $result) { $result = -1; }
  if ($result <= 0) {
    print STDERR "\n" . $0 . ": CHYBA: " . $dbh->errstr . "\n";
    $dbh->rollback();
    return ISHN_ERR_INTERNAL;
  }

[download]
This is the rest of my subroutine: 
  $statement = q{UPDATE results
                 SET status = ?, verze = ?
                 WHERE host = ? AND app = ?;};
  $result = $dbh->do($statement, undef, $status, $version, $host, $app
+);
  if (! defined $result) { $result = -1; }
  if ($result <= 0) {
    print STDERR "\n" . $0 . ": CHYBA: " . $dbh->errstr . "\n";
    $dbh->rollback();
    return ISHN_ERR_INTERNAL;
  }
  $statement = q{INSERT INTO history
                 (host, app, status, verze)
                 VALUES (?, ?, ?, ?);};
  $result = $dbh->do($statement, undef, $host, $app, $status, $version
+);
  if (! defined $result) { $result = -1; }
  if ($result <= 0) {
    print STDERR "\n" . $0 . ": CHYBA: " . $dbh->errstr . "\n";
    $dbh->rollback();
    return ISHN_ERR_INTERNAL;
  }
  $result = $dbh->commit();
  if (! defined $result) { $result = -1; }
  if ($result < 0) {
    print STDERR "\n" . $0 . ": CHYBA: " . $dbh->errstr . "\n";
    $dbh->rollback();
    return ISHN_ERR_INTERNAL;
  } else { return ISHN_OK; }
}

[download]

In reply to Re^2: Variable scope & subroutines by Nyyr
in thread Variable scope & subroutines by Nyyr

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