sybperl-l Archive

From: <Sam dot Storie at EmersonProcess dot com>
Subject: DBlib->dbpoll() behaving differently for ASE 12.5.3 w/ Sybperl-2.17 and ASE 15.0.1 w/ Sybperl-2.18
Date: Nov 21 2006 8:41PM

Hello. I have an issue I've noticed when trying to migrate a backup
script I wrote to work with ASE 15.0.1. In my script I use the dbpoll()
function within Sybase::DBlib to monitor the results from a dbcc command
and report if it takes longer than I expect. What's happening is that
when I use sybperl 2.18 built against ASE 15.0.1, the call to dbpoll()
never returns with a result like it's supposed to. To help demonstrate
this I broke this down into a simple perl script:

-----8<-----8<-----8<------
dbpoll_test.pl:

#!/usr/bin/perl -w

use strict;
use Sybase::DBlib;

my (
	$dbh,
	$dbh2,
	$result,
	$elapsed
);

$dbh = Sybase::DBlib->dblogin("LOGIN", "PASSWD", "SERVER");

$dbh->dbcmd("waitfor delay '00:00:03'\nselect \@\@version");
$dbh->dbsqlsend();

$elapsed = 0;

while($elapsed < 10) {
	sleep(1);
	$elapsed++;

	($dbh2, $result) = $dbh->dbpoll(100);

	if($dbh2 && $result == DBRESULT) {
		print "Result completed successfully: $elapsed\n";
		$elapsed = 100;
	}

}

print "Script done: $elapsed\n";
-----8<-----8<-----8<------

This script should issue a query that waits for 3 seconds, then selects
the version of the server. To monitor the query, I use the dbpoll call
to wait up to 10 seconds and based on the output I can verify that
dbpoll behaved as I expected.

   --------------------------
   Here's the output when run on my ASE 12.5.3 server.

   $ /usr/bin/perl -MSybase::DBlib -e 'print
"$Sybase::DBlib::Version\n"'
   This is sybperl, version 2.17

   Sybase::DBlib $Revision: 1.59 $ $Date: 2004/06/11 13:04:09 $

   Copyright (c) 1991-2001 Michael Peppler

   DB-Library version: Sybase DB-Library/12.5.1/P-EBF11758 ESD
#2/DRV.12.5.1.0/SPARC/Solaris 2.8/BUILD1251-002/OPT/Tue Mar  9 18:42:24
2004

   $ ./dbpoll_test.pl
   Result completed successfully: 3
   Script done: 100
   --------------------------

The output is telling me that my loop only needed to wait 3 seconds for
the result to appear, which is good. If I run this script, using this
environment, against my 15.0.1 server I *also* get these results (which
is also good).

Now if I change and run the script from within my 15.0.1 environment
against both servers I get results like this:

   --------------------------
   Here's the output when run on my 15.0.1 server:

   $ perl -MSybase::DBlib -e 'print "$Sybase::DBlib::Version\n"'
   This is sybperl, version 2.18

   Sybase::DBlib $Revision: 1.61 $ $Date: 2005/03/20 19:50:59 $

   Copyright (c) 1991-2001 Michael Peppler

   DB-Library version: Sybase DB-Library/15.0/P-EBF13716 ESD
#4/DRV.15.0.1/SPARC/Solaris 8/BUILD1500-074/OPT/Mon Jun  5 01:23:01 2006

   $ ./dbpoll_test.pl
   Script done: 10
   --------------------------

As with the first test, I get this same result when I run it against my
15.0.1 and 12.5.3 servers. From what I can tell, all the other aspects
of Sybperl I use work correctly, but dbpoll() isn't. 

Anyone have any ideas on what I can try here? Thanks.

-Sam
 
---
Sam Storie
Database Administrator
Rosemount Incorporated
Emerson Process Management