$self->EventTags->find_or_create({ event=>$self->id, tag=>$v,  });


in EventTags.pm:

__PACKAGE__->add_unique_constraint(
    ['event','tag']
);


error:
DBIx::Class::ResultSet::find_or_create(): Can't find unless a primary key is defined or
unique constraint is specified at
libs/saltem-schema/lib/Saltem/Schema/Result/Event.pm line 132