id	summary	reporter	owner	description	type	status	component	version	severity	resolution	keywords	cc	stage	has_patch	needs_docs	needs_tests	needs_better_patch	easy	ui_ux
21705	Generic Relations fail to detect validation error appropritely	mo_ttds@…	nobody	"Hi. When using a GenericRelation on a Model to create a M2M generic relation between two other models, with a '''unique_together''' attribute on the relation. admin site fails to detect '''uniqueness-validation''' and instead of reporting a unique violation validation error it raises an '''IntegrityError''' e.g. IntegrityError: columns tag_id, object_id are not unique

here is the case:
{{{
class Tag(models.Model):
    slug = models.SlugField(max_length=100)
    
    def __unicode__(self):
        return self.slug

class News(models.Model):
    title = models.CharField(max_length=100)
    
    def __unicode__(self):
        return self.title
    
class Tagger(models.Model):
    class Meta:
        '''unique_together = ('tag', 'object_id')'''
    
    tag = models.ForeignKey(Tag)
    content_type    = models.ForeignKey(ContentType)
    object_id       = models.PositiveIntegerField()
    content_object  = generic.GenericForeignKey()
}}}

and creating the admin objects like this:

{{{
class TagAdmin(admin.ModelAdmin):
    list_display = ('slug',)

class TabularTagInline(generic.GenericTabularInline):
    model = models.Tagger
    extra = 2

class NewsAdmin(admin.ModelAdmin):
    list_display = ('title', )
    inlines = (TabularTagInline,)

admin.site.register(Blog, BlogAdmin)
admin.site.register(Tag, TagAdmin)
}}}
"	Bug	closed	contrib.admin	1.6	Normal	invalid	AdminSite, GenericRelation, unique_together, IntegrityError		Unreviewed	0	0	0	0	0	0