DBIx::Class 尝试使用 ->create() 时出现未定义值异常

Question

I'm trying to create a new row using DBIx::Class from within Catalyst, with the following code:

$c->model('Session')->resultset('UserPreference')->create(
                {
                 appname => 'rss_reader',
                 username => $username,
                 data => $data,
                },
               );

But, I hit this error every time:

Caught exception in App::Controller::rss->dbo "Can't call method "resolve" on an undefined value at /etg/source/Linux/pkg/perl-5.8.8/lib/site_perl/5.8.8/DBIx/Class/Row.pm line 1309."

I see a few mailing lists talking about this error being thrown as an incorrect blanket error when the query fails for whatever reason (perms, constraints,etc.), but it looks just fine AND even running with DBIC_TRACE=1, I don't even see the generated query in my console.

I should mention I don't think there's something bad with the permissions,etc. since using the database handle manually works:

my $stm=$c->model("Session")->storage->dbh->prepare("insert into user_preferences (username,appname,data) values ('mphillip','rss_reader','cookies')"); $stm->execute(); 

Answer 1

Have you tried update_or_create instead of create ? If a row exists create will fail.