sybperl-l Archive

From: Michael Peppler <mpeppler at peppler dot org>
Subject: CTLib Callback Msg; can this access the SQL statement being execu ted
Date: May 17 1999 1:17PM

Ruth Geever writes:
 > Hello,
 > 
 > I'm using Sybperl with Sybase Open Client 11.1.1;
 > When an error occurs, I want to display the SQL statement that caused the
 > error. However, I cannot access the SQL statement that caused the error in
 > the callback subroutine.

Unfortunately there is no equivalent to dbstrcpy() in Client Library,
so there is no really easy way to do this.

There are a number of alternate ways to achieve this, however. The
most painless (and mostly transparent to your users) is to write a
module that inherits from Sybase::CTlib and that overloads
ct_execute(), storing the $sql in the $dbh before the execute.

Something like

package My::CTlib;

use Sybase::CTlib;

use strict;
use vars qw($VERSION @ISA @EXPORT @EXPORT_OK);

require Exporter;
require AutoLoader;

@ISA = qw(Exporter AutoLoader Sybase::CTlib);
@EXPORT = @Sybase::CTlib::EXPORT;
$VERSION = '1.00';

sub new {
    my ($package, $user, $pwd, $server, $app, $attr) = @_;

    # Pre-allocate space for the SQL text in the $dbh struct.
    if ($attr) {
        $attr->{SQL} = '';
    else {
        $attr = {SQL => ''};
    }

    $package::SUPER->new($user, $pwd, $server, $app, $attr);
}

sub ct_execute {
    my $dbh = shift;
    my $sql = shift;

    $dbh->{SQL} = $sql;   # Store the $sql in the dbh...

    $dbh::SUPER->ct_execute($sql);  # call the real ct_execute;
}

1;

__END__

Place the above in a file in My/CTlib.pm.

Now in your program you do:

use My::CTlib;

ct_callback(CS_SERVERMSG_CB, \&msgCB);

$dbh = new My::CTlib $user, $pwd, $server;

$dbh->ct_execut("...");

etc...


sub msgCB
{
my $ctlib = shift;
my ($number, $severity, $origin, $layer, $server, $proc,
$msg, $osmsg) = @_;

	my $q = new CGI;
	print $q->header(),
		$q->start_html(),
		$q->h1('Sybase Error'),
		'',
		'',
		'',
		'';
	print ''
if defined($osmsg);
	# Print out the SQL:
        print '';

	print	'
Open Client Message:
Message Number:
LAYER = ',$layer,' ORIGIN =
',$origin,'
SEVERITY = ',$severity,' NUMBER =
',$number,'
Message String:
',$msg,'
Operating System Error:
',$osmsg,'
SQL:
', $ctlib->{SQL}, '
';

	$q->end_html();
	exit;
	return CS_SUCCEED;
}


I hope this helps a little bit....

Michael
-- 
Michael Peppler         -||-  Data Migrations Inc.
mpeppler@peppler.org    -||-  http://www.mbay.net/~mpeppler
Int. Sybase User Group  -||-  http://www.isug.com
Sybase on Linux mailing list: ase-linux-list@isug.com