Let me echo what the other two (so far) respondents have mentioned .. we gotta see some code or all we're doing is waving our hands (or arms).

However, based on 'fails after more than 17', I'm guessing it might be that some buffer is getting full and there are problems allocating a second buffer. You've turned up the DBI->trace value, right? Does that tell you anything?

• its not really dieing, but because a lot is getting written to error logs (for whatever reason), takes quite a while.
• if you arent finish() ing your query handles within the loop, your program may be eating too many resources for mysql to handle, based on your configuration for max temp tables, etc. From Programming the Perl DBI (O'Reilly), Page 111: "After execute() returns successfully, the database has not necessarily completed the execution of the SELECT statement..."

If we could see your code, we would be able to tell you more. Without code, it's just guesswork.

Please try to isolate the offending code, and post it here.

For more on this subject, please see Before asking a database related question ... in Tutorials.

apache error_log shows no error!
perl.exe still runs ...

the select statement
SELECT table1.id, table1.id2, table1.id3 ,table2.name 
FROM table2, table1
WHERE table1.id = 'something' 
and 
table1.id=table2.id


my ($result_ref, $columnNames_ref, $numFields)  = fetchRowArray($dbh, 
+$sql);
... 
sub fetchRowArray($$){
  my $dbh = shift;
  my $sql = shift;
  my $sth = $dbh->prepare($sql) or meldeFehler("Statement could not pr
+epared");
  $sth->execute() or meldeFehler("Statement could not executed"); 
  my $columnNames;
  $columnNames = $sth->{NAME}; 
  my $numfields;
  $numfields = $sth->{NUM_OF_FIELDS};
  my (@matrix) = ();
  while (my @ary = $sth->fetchrow_array())
    {
      push(@matrix, [@ary]); 
    }
  $sth->finish();
  return \@matrix, $columnNames, $numfields; 
 
}
[download]

I don't see any reason for your code to hang in this snippet. Maybe you can optimize it a bit, as in the example below, but there is nothing so wrong that it could cause a halt.

sub fetchRowArray($$){
  my $dbh = shift;
  my $sql = shift;
  my $sth = $dbh->prepare($sql) 
    or die("statement can't be prepared");
  $sth->execute() 
    or die("Statement can't be executed"); 
  my $columnNames = $sth->{NAME}; 
  my $numfields= $sth->{NUM_OF_FIELDS};
  my $matrix) = $sth->fetchall_arrayref();
  return $matrix, $columnNames, $numfields; 
}
[download]

What is not clear in your request is this: you say that your code stops after 17 loops and later that the MySQL log shows 17 queries. Therefore, maybe the reason for hanging is not in this loop, but some other place in your script.

The candidates for further scrutiny are, then, your sub meldeFehler and the point from where your are calling fetchRowArray.

Please clarify what you mean by loop. If you mean that it hangs after 17 successful queries, then you may have a memory problem. If you mean that it hangs when the records are more than 17, then I don't see the cause here.

As a piece of practical advice, I would recommend to run this script from the command line, to see if the result is what you expected, and put some print statements in the critical points (printing, for example, "inside meldeFehler", "before calling fetchRowArray", and so on) so that you get a clear idea of where exactly the code stops.

HTH

You can use DBI method fetchall_arrayref()

my $matrix = $sth->fetchall_arrayref();
[download]

instead of

  my (@matrix) = ();
  while (my @ary = $sth->fetchrow_array())
  {
     push(@matrix, [@ary]); 
  }    
}
[download]

Can you show a part of your script which generates an HTML page?

      
--------------------------------
SV* sv_bless(SV* sv, HV* stash);

Thanks first for hints ....
The code works fine on Linux!!!!
And the cgi (running under Windows with the Apache server) works well with the Linux mysql server.
It must be the communication between perl and mysql in Windows , or?