I'm trying to query a database based on user input tags. The number of tags can be from 0-5, so I need to create the query dynamically.
So I have a tag list, tag_list, and I want to query the database:
design_list = Design.objects.filter(Q(tags__tag__contains = "tag1") and Q(tags__tag__contains = "tag2") and etc. etc. )
How can I create this feature?
You'll want to loop through the tag_list and apply a filter for each one.
tag_list = ['tag1', 'tag2', 'tag3']
base_qs = Design.objects.all()
for t in tag_list:
base_qs = base_qs.filter(tags__tag__contains=t)
This will give you results matching all tags, as your example indicated with and
. If in fact you needed or
instead, you will probably need Q objects.
Edit: I think I have what you're looking for now.
tags = ['tag1', 'tag2', 'tag3']
q_objects = Q() # Create an empty Q object to start with
for t in tags:
q_objects |= Q(tags__tag__contains=t) # 'or' the Q objects together
designs = Design.objects.filter(q_objects)
I tested this and it seems to work really well.
Edit 2: Credit to kezabelle in #django on Freenode for the initial idea.