How can I refactor this django query to not select each individual object?
Here's my view:
def rsvp_list(request, id, template="rsvp/rsvp_list.html"):
rsvp = RSVP.objects.get(id=id)
return render_to_response(template, {
'attendees': rsvp.attendee_set.all().order_by('email__first_name'),
}, context_instance=RequestContext(request))
and here's my template:
{% for attendee in attendees %}
{{ attendee.email.get_name }}{{ attendee.guests }}
{% endfor %}
When the request is run, the template then runs a query for each attendee to get their first and last name (get name just puts the two together). Here's an example query that django fires from the template:
SELECT `rsvp_email`.`id`, `rsvp_email`.`added`, `rsvp_email`.`first_name`, `rsvp_email`.`last_name`, `rsvp_email`.`address` FROM `rsvp_email` WHERE `rsvp_email`.`id` = 1038
How can I retrieve the first and last name of each attendee is the first query without looping through it 400 times in the template?
I should have read a bit further in the documentation.
In order to reduce the queries that are going to happen on related object later, just use select_related. So my query becomes:
attendees = rsvp.attendee_set.select_related().all().order_by('email__first_name')
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