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