Question

I’m creating a website about baseball player for learning purpose. I’m stock in how to handle the foreign keys.
Here is my model:

class Player_Bios(models.Model):

   mlb_id           = models.SlugField(unique=True)    
   name             = models.CharField(max_length=50) 
   last             = models.CharField(max_length=50)
   middle           = models.CharField(max_length=50, blank=True)
   jersey           = models.CharField(max_length=5)
   def __unicode__(self):
        return self.mlb_id


class Stat (models.Model):
   player_id       = models.ForeignKey('Player_Bios')
   year            = models.IntegerField(max_length=50)
   h               = models.IntegerField(max_length=50)
   2h              = models.IntegerField(max_length=50)



   def __unicode__(self):
       return self.stat_id

So I’m able to go get the players stat, but how do I save them to database?

Example of what I want to do. I was able to collect and save all of the players that I want to have on my website and saved all of their bios. The only thing that I need is the players Career Stat.

from player_bios.models import *

year = "2012"     # I use variable in this example because I don't want to put all my code
h    = 180        #But think that I have this info
2h   = 30
st= Stat(player_id=, year=year,h=h,2h=2h)  #I don't know what to use on player id because                     that's the foreign key
st. save            

UPDATE:

I’m still having issues saving the data to the database.
Here is my code:

from django.core.management.base import BaseCommand, CommandError
from player_bios.models import *
import urllib2
import json
import string
import re


DR_ID = [u'430947', u'499864', u'405395']
stint = ["player_id","sport_code","ab","league_full","bb","ops","hr","season","ao","team_id",
    "go","cs","league_short","avg","go_ao","sport_id","team_full","league","sport","gidp",
    "d","g","team_abbrev","league_id","h","ibb","team_seq","sf","sac","team_short","r","so",
    "t","rbi","sb","slg","tb","hbp","obp"]
st = {}

class Command(BaseCommand):

for i in DR_ID:
    url = ("http://mlb.mlb.com/lookup/json/named.sport_hitting_composed.bam?game_type='R'&sport_code='mlb'&sport_code='aaa'&sport_code='aax'&sport_code='afa'&sport_code='afx'&sport_code='asx'&sport_code='rok'&sort_by='season_asc'&player_id="+i+"&sport_hitting_composed.season=2013")
    res = urllib2.urlopen(url)
    data = json.load(res)
    numberofseasons = data['sport_hitting_composed']['sport_hitting_tm']['queryResults']['totalSize']
    numberofseasons= int(numberofseasons)
    row = 0

    while row < numberofseasons:

        for x in stint:

            data2 = data['sport_hitting_composed']['sport_hitting_tm']['queryResults']['row'][row][x]
            st[x]=data2


        row +=1
        p_id = p=Player_Bios.objects.get(mlb_id=i)
        p_id_st=str(p_id)
        bat_id = (st['season']+st["team_id"])
        bat_id = p_id_st + bat_id
        c = BatStat(player_id_id= p_id.mlb_id,bat_stat_id=bat_id, sport_code = st["sport_code"],ab=st['ab'],league_full=st['league_full'],bb=st['bb'],ops=st['ops'],hr=st['hr'],season=st['season'],ao=st['ao'],
                    team_id=st['team_id'],go=st['go'],cs=st['cs'],league_short=st['league_short'],avg=st['avg'],go_ao=st['go_ao'],sport_id=st['sport_id'],team_full=st['team_full'],
                    league=st['league'],sport=st['sport'],gidp=st['gidp'],d=st['d'],g=st['g'],team_abbrev=st['team_abbrev'],league_id=st['team_id'],h=st['h'],ibb=st['ibb'],
                    team_seq=st['team_seq'],sf=st['sf'],sac=st['sac'],team_short=st['team_short'],r=st['r'],so=st['so'],t=st['t'],rbi=st['rbi'],sb=st['sb'],slg=st['slg'],tb=st['tb'],
                    hbp=st['hbp'],obp=st['obp'])
        c.save()   

I get the following error:

django.db.utils.IntegrityError: (1452, 'Cannot add or update a child row: a foreign key      constraint fails (`player_bios_info`.`player_bios_batstat`, CONSTRAINT `player_id_id_refs_id_ee2da61` FOREIGN KEY (`player_id_id`) REFERENCES `player_bios_player_bios` (`id`))')

In the model I have the player_id, but on the database I see it as player_id_id.
Thanks in advance

Answer 1

You need to create form so that it’s easy for you to select player. If you want to add just like what you did manually, it will be difficult for you.

forms.py

class StatForm(forms.ModelForm):
    class Meta:
        model = Stat

    def __init__(self, user, *args, **kwargs):
        super(StatForm, self).__init__(*args, **kwargs)
        self.fields['player_id'].queryset = Player_Bios.objects.filter()

views.py

def add_stat(request):
    if request.method == 'POST':
        form = StatForm(request.POST)
        if form.is_valid():
            form.save() 
return render(request, 'add_stat.html', {
    'form': StatForm(),
}) 

add_stat.html

<form method="post">{% csrf_token %}
    {% for field in form %}
        {{field}}<br/>
    {% endfor %}
    <input type="submit" value="Save Stat">
</form>