I have the following Models in Django.
from django.db import models
#Show DB Table Model
class Shows(models.Model):
show_key = models.CharField(primary_key=True, max_length=7)
show_date = models.DateField(blank=True, null=True)
show_venue = models.CharField(max_length=50, blank=True, null=True)
show_city = models.CharField(max_length=50, blank=True, null=True)
show_state = models.CharField(max_length=3, blank=True, null=True)
show_country = models.CharField(max_length=3, blank=True, null=True)
class Meta:
managed = False
db_table = 'shows'
#Songs DB Table Model
class Songs(models.Model):
song_key = models.CharField(primary_key=True, max_length=8)
show_key = models.ForeignKey('Shows', models.DO_NOTHING, db_column='show_key', blank=True, null=True)
song_name = models.CharField(max_length=100, blank=True, null=True)
song_set = models.CharField(max_length=20, blank=True, null=True)
song_track = models.IntegerField(blank=True, null=True)
song_encore = models.IntegerField(blank=True, null=True)
song_segue = models.CharField(max_length=1, blank=True, null=True)
song_notes = models.CharField(max_length=100, blank=True, null=True)
song_cover = models.CharField(max_length=50, blank=True, null=True)
song_with_guest = models.CharField(max_length=50, blank=True, null=True)
class Meta:
managed = False
db_table = 'songs'
I am trying make a query that will find all objects meeting a certain criteria, ie:
Shows.objects.filter(show_date__year=2000)
This above query would return multiple objects.
I need to take it a step further and pull all of the information from the Songs table/model relating to the filtered Show objects. The models are related in the sense that the "show_key" is a primary key / foreign key relationship and is one to many.
I also need to package all of the found data up into a usable form that I can iterate through and send to a jinja2 template.
For example:
{% for item in query_results %}
<ul>
<li>item.show_date</li>
<li>item.show_venue</li>
<li>item.show_city</li>
<li>item.show_state</li>
<li>item.show_country</li>
</ul>
<ul>
{% for song in item %}
<li>song.song_name</li>
<li>song.song_set</li>
<li>song.song_track</li>
<li>song.song_encore</li>
<li>song.song_segue</li>
<li>song.song_notes</li>
</ul>
{% endfor %}
Thanks in advance. Brent
Seems like what you're trying to do is follow a FK relationship backwards .
This is what it should look like in the template:
{% for show in query_results %}
<ul>
<li>show.show_date</li>
<li>show.show_venue</li>
<li>show.show_city</li>
<li>show.show_state</li>
<li>show.show_country</li>
</ul>
<ul>
{% for song in show.entry_set.all %}
<li>song.song_name</li>
<li>song.song_set</li>
<li>song.song_track</li>
<li>song.song_encore</li>
<li>song.song_segue</li>
<li>song.song_notes</li>
</ul>
{% endfor %}
This will actually force jango to issue one SQL query for every show. If you have too many it can be a pain. To avoid this you can tell Django to select related songs data when it queries for the shows. This can save you a lot of SQL queries.
Shows.objects.select_related(Songs).filter(show_date__year=2000)
I finally figured it out!
First I queried the Shows model/table and saved the results to query_results:
query_results = Shows.objects.filter(show_date__year=2018)
Then in my Jinja Template
{% for show in query_results %}
<ul>
<li>{{show.show_date}}</li>
<li>{{show.show_venue}}</li>
<li>{{show.show_city}}</li>
<li>{{show.show_state}}</li>
<li>{{show.show_country}}</li>
</ul>
<ul>
{% for song in show.songs_set.all %} #This is the key, calling the related "shows_set.all" This grabs the related objects from the Songs table/model
<li>{{song.song_name}}</li>
<li>{{song.song_set}}</li>
<li>{{song.song_track}}</li>
<li>{{song.song_encore}}</li>
<li>{{song.song_segue}}</li>
<li>{{song.song_notes}}</li>
{% endfor %}
</ul>
{% endfor %}
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