Getting data to SQLite database in Django

Question

I'm new to Python and Django and I have ran into problems, I couldnt find answer to. I'm using Django 1.7 with SQLite3 and Python 3.4. I'm trying to make a sports league table, by getting data from a third party website and posting it to my own. So far I can get the needed data from the web. I have set up the tables to my SQLite db and can write the data, which I manually enter, to my page with django-tables2 app. The problem is that I cant figure out, how to automate my script so it could automatically write the data to the tables in SQLite.

Here is my models.py file:

from django.db import models
import django_tables2 as tables
from django.db import connection

class Ranking(models.Model):
    Team_name = models.CharField(max_length=25,unique=True)
    League = models.CharField(max_length=15,)
    League_points = models.CharField(max_length=3,)

# If I just add the rows from def te() to the end of the script and run the 
#server with manage.py runserver, it adds values "Team name", "First league", 
#"11" to the correct places, but closes the server instantly, because these 
#values have been added already.

    def te():
        cursor = connection.cursor()

        cursor.execute("""INSERT INTO EEtabel_ranking ('Team_name', 'League', 'League_points') VALUES (?, ?, ?)""", ("Team name", "First league", "11"))

    def __str__(self):

        return ' '.join([
            self.Summoner_name,
            self.League,
            self.League_points,
        ])

# This is for creating the table with data from database
class SimpleTable(tables.Table):
    class Meta:
        model = Ranking

Now, what I'd like to achieve, is to get the data to the table and update it once a day. So if visitors go to my page, they see the latest updated table and they dont trigger a new update. The updates should happen at fixed times.

Here is the script, which helps me to get data from the web:

from wsgi.openshift.myapp import MyAppClient  # MyApp is an app, which connects to the website, I'm making a connection to, to get data from there.

list_of_team_names = ['team1', 'team2', 'team3', 'etc']
client = MyAppClient.MyAppClient(key, "league_name")


team = client.search(list_of_team_names)
for x in list_of_team_names:
    print(team.name)
    league = client.league_data()
    print(league.tier)
    print(league.entries.leaguePoints)
    team = client.next()

#What this does, is that it searches the results of the teams in the "list_of_team_names".
#And gets the results one by one.

What the result looks like (an example): Team1 First League 34 Team2 First league 45 Team3 First league 10 etc.

So to sum up that horribly long story - my questions in short:

1)How to get the data to the SQLite database correctly?

2)How to make it so the data gets overwriten?

I mean that if I already have Team1 with 34 points in the table. and after recieving 3 points, my table wouldnt look like: Team1 34 pts, Team1 37 pts. It should replace the previous records.

3)How to get the data to update itself once a day (or hour or twice a day (custom time))?

I thank you in advance and hope that one day I'll get more experienced, so I wouldnt have to ask these kind of silly questions again. :P

Answer 1

You are doing it wrong^TM

Platforms like Django take provide Object-relation mappers that allow you to abstract away direct interaction with the database and work with programming objects instead.

To be quite honest, I have no idea if you are writing the database query correctly, and the be brutally honest, I don't care. The Django-ORM exists for a very good reason, it makes things easier. Could you craft a raw database query to insert rows into a django databse, probably, but this is much easier:

from wsgi.openshift.myapp import MyAppClient

list_of_team_names = ['team1', 'team2', 'team3', 'etc']
client = MyAppClient.MyAppClient(key, "league_name")

team = client.search(list_of_team_names)
for x in list_of_team_names:
    ranking = Ranking(
      Team_name = team.name
      League = league.tier
      League_points = league.entries.leaguePoints
    )
    ranking.save()

models.py exists to define the objects you want to work with, so that by instantiating an object you prepare it for the database (which is why you need to explicitly call save in this case).

We can could instead create and save, like so:

ranking = Ranking.objects.create(
      Team_name = team.name
      League = league.tier
      League_points = league.entries.leaguePoints
    )

or, directly get an object, or create if none exists:

was_created, ranking = Ranking.objects.get_create(
      Team_name = team.name
      League = league.tier
      League_points = league.entries.leaguePoints
    )

Which is probably much shorter and clearer than the related SQL queries and code required to check if objects exists and return them.