django database if 2 exists code example
Example 1: rest api django return value if exists in another table
class PostSerializer(serializers.ModelSerializer):
replied = serializers.SerializerMethodField('has_replies')
def has_replies(post):
return post.replies.filter(owner=self.context["request"].user).exists()
class Meta:
fields = ('id', 'name', 'replied')
Example 2: rest api django return value if exists in another table
class PostList(generics.ListAPIView):
...
def get_queryset(self):
Post.objects.all().extra(select={
'current_user_replies_count': 'SELECT COUNT(*) FROM <reply table> WHERE' +
'post_id=posts_post.id AND owner_id = %s'
},select_params=(request.user.id,))