[Dbix-class] Problem with DBIx::Class::Schema::Loader or

[James Masters]

Just to give feedback on this, I have completely reinstalled Perl using
IndigoPerl (installing all the modules for DBIx was a long winded business I
can tell you).  And that didn't work so then I completely reinstalled Active
State Perl.

But now it's even worse - the DBIx Loader itself is now not working AND
produces a whole load of these unreferenced scalar messages.  I've tried a
variety of different tinkerings with different modules from active state and
Winnipeg without success.  I haven't tried recompiling DBI with gcc because
I'm not even sure what that means.  I looked up what gcc is but I thought
Perl was an interpreted language so I can't see how I can compile the DBI
module.  No doubt there is an obvious answer to this and all you Perl gurus
are raising your eyes to the heavens but I'd rather not experience the
learning curve if I can avoid it - I have spent days on this now without
getting too far so I'm going to revert to Class::DBI and see if I can get
going quicker with that.

There was one interesting point though in case this of any use for
developers.  Although it popped up unreferenced scalar messages, the DBI
Loader loaded one table but failed as soon as it started my next table.
Here's the error:

Can't use an undefined value as an ARRAY reference at
C:/perl/site/lib/DBIx/Class/Schema/Loader/DBI.pm line 99.

So I had a tinker with this and discovered that if I added a single print
statement here:


# Returns an arrayref of column names
sub _table_columns {
    my ($self, $table) 
    my $dbh 
    if($self->{db_schema}) {
        $table     }

my $statement     my $sth     $sth->execute;
print "Num values found ".@{$sth->{NAME_lc}}."<br>";
    return \@{$sth->{NAME_lc}};
}

it works and loads all the tables!!  Bizarre.  Still getting unreferenced
scalar messages, though.  I think this shows that it is some kind of
threading error.

thanks,

James.
  -----Original Message-----
  From: dbix-class-bounces at lists.rawmode.org
[mailto:dbix-class-bounces at lists.rawmode.org]On Behalf Of James Masters
  Sent: 25 August 2006 11:49
  To: dbix-class at lists.rawmode.org
  Subject: Re: [Dbix-class] Problem with DBIx::Class::Schema::Loader or


  Thanks for your helpful further tips.  The missing module was
Module::Find.  I think this was a red herring due to a mistake in where I
had placed one of my hand-made modules.  I've reworked this and now
   ->load_classes does work so Module::Find is not needed apparently.  i.e.
you were right; it was my mistake in the way I set up the schema modules.

  On lower case column names, OK thanks.   I understand.

  On this unreferenced scalar, issue. I have upgraded DBI from 1.5 to 1.52
but this unfortunately has not fixed it.  I've upgraded almost all other
modules to the latest win32 releases found at Winnipeg Uni too but without
success.  Googling, I can see this error message crops up a lot all over the
place and everyone seems to relate it to problems with threading.  In fact,
many times it's attributed to a bug in PERL itself although I think these
might be old posts.  (Incidentally I'm running A/S PERL "v5.8.6 built for
MSWin32-x86-multi-thread").  Perhaps one of the modules I'm running is not
thread-safe for win32.  There are also some vague remarks about having
threads "enabled".  So I'm wondering if I can disable threads somehow, maybe
via an env. variable.  I can't find out how, though.  Does anyone know if
this is possible?

  I have already had a quick look at SQL/Abstract/Limit but I'm afraid I am
at the limit of my knowledge and I just wouldn't dare to try to tinker with
it.  The code in there is meaningless to me.  It's V0.12 and the line says:

  return $self->_find_syntax_from_database($db) if $db;

  Just in case, I have reinstalled SQL-Abstract and SQL-Abstract-Limit using
PPM from Winnipeg Univ.  Also, I've checked & the versions of these that I
have are the same as the latest that CPAN shows.

    -----Original Message-----
    From: dbix-class-bounces at lists.rawmode.org
[mailto:dbix-class-bounces at lists.rawmode.org]On Behalf Of Brandon Black
    Sent: 24 August 2006 23:21
    To: dbix-class at lists.rawmode.org
    Subject: Re: [Dbix-class] Problem with DBIx::Class::Schema::Loader or





    On 8/24/06, James Masters <james at masters.me.uk> wrote:
      Thanks for the advice.  I have been re-reading the documentation and
have made some progress by using the Loader Debugger.

      Firstly, let me reply to your 2 points.  Of course, I did first try to
use ->load_classes.  This didn't work - the error said I was missing a
module; I can't remember the name of it now but I couldn't find a win32
version of it so gave up

    First, you should stop right there and work on that problem.  What is
this missing module, why is it missing, and can it be fixed?  This doesn't
sound sane/normal.  I've haven't heard about people who cannot use
load_classes.  And no, "use MG::Schema::Foo" is *not* an adequate
substitute.



      Anyway, with the debugger, I have learnt that the Loader was working
fine. I can see all the tables, columns and PKs being loaded.  Also I got
the resultsets to work - the problem was that I was specifying CountryCode
(which is indeed the correct name of my column) but to get it to work I have
to use lower case "countrycode".  Someone has told me that this is because
MySQL columns are not case-sensitive and all columns are stored in lower
case.  [ Still, I don't think this is ideal behaviour personally as I like
my "cased" column names.  Wouldn't a better behaviour be for the methods to
accept any case?  Not sure if possible as might mess up other database
interfaces - just wondering. ]

    The Loader currently does force all column names to lower case.  Normal
DBIx::Class lets you specify them however you like, and honors that
specification.  The decision to lowercase them all in Schema::Loader just
makes the code *much* simpler than dealing with all of the cross-vendor case
issues that exist for what Loader is doing.  At least for the time being, if
you want CamelCase column names in DBIx::Class, you have to do it for
yourself.



      However, I am left with a problem.  The following error:

      Attempt to free unreferenced scalar: SV 0x1fa7a5c, Perl interpreter:
0x224234 at C:/Perl/site/lib/SQL/Abstract/Limit.pm line 325.

      occurs every time I attempt to use a resultset.  Tinkering has
established that it occurs with each of the following lines.

      my @livecountries 'Y');
      my $m       my @allcountries       my $country        my $r       my $p 
      If I put all 6 lines, it occurs 6 times.  It happens if this is the
last thing in the script.

      This only happens when the schema is loaded via Loader - it did not
appear when the schema was loaded via my manually created module. The Loader
debugger does not give any clues.  If anyone can point me in the right
direction for further reading/investigation, I'd be very grateful.

    The error itself is pointing you somewhere.  What's on line 325 of
S::A::L? (and what version do you have installed from where?).

    -- Brandon


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