sybperl-l Archive

From: Michael Peppler <mpeppler at MBAY dot NET>
Subject: Re: message_handler
Date: Jan 21 1998 7:56PM

Naveen_Rajavasireddy@ACML.COM wrote:
> 
> 1) Installed the message_handler in my program.
> 2) Insert SQL statement 1 for table A
> Before the execution of next statement, I create a deadlock situation by
> running a program in a
> different session.
> 3) Insert SQL statement 2 for table B
> 4) The above command becomes a deadlock victim and fails.
> 5) Program loops back and starts from step 2 on looking at the 1205 message
> 
> My problem is that after the fail on step 3, my variables from the message
> handler are still that of deadlock
> even though, I insert into the database successfully.

How do you check for the 1205 error in the main body of your code?

I've usually done something like:

if($dbh->dbsqlexec() == FAIL) {
	if( $error = 1205 ) {
		goto try_again;
	}
}

Of course, you could also do something a little more fancy if
you have sybperl 2.09:

$dbh = new Sybase::DBlib user, pwd, server, undef, {LastError => 0 };

The in the message handler, do

$dbh->{LastError} = $msg_no;

(the $dbh is the first param to the message handler).

Then you can check $dbh->{LastError} when dbsqlexec or dbresults
fail, without the need for a global variable.

This does not work in 2.08 and before because the $dbh parameter that
is passed to message_handler is a copy of the original $dbh.

Michael
--
Michael Peppler       -||-  Data Migrations Inc.
mpeppler@datamig.com  -||-  http://www.mbay.net/~mpeppler