[Answer]-In Django, do I need syncdb after I added a method to a model?

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1👍

It works for me…

(dev) C:\work\dev\datakortet>cat maint\models.py
# -*- coding: utf-8 -*-

from django.db import models
from django.contrib.auth.models import User

class WordList(models.Model):
    list_id = models.CharField(max_length=32, primary_key=True, default='42')
    title = models.CharField(max_length=50)
    user = models.ForeignKey(User, editable=False)
    #...

    def length(self):
        return len([])

calling syncdb because I didn’t have the model in the db..

(dev) C:\work\dev\datakortet>python manage.py syncdb
Installing custom SQL ...
Installing indexes ...
Installed 0 object(s) from 0 fixture(s)

Synced:
...
 > datakortet.maint
...

(dev) C:\work\dev\datakortet>cat tstwordlist.py
from django.contrib.auth.models import User
from maint.models import WordList

usr = User.objects.get(pk=1)
#WordList.objects.create(list_id=42, title='foo', user=usr)

wordlists = WordList.objects.filter(user=usr)
for w in wordlists:
    print dir(w)
    print w.length()


(dev) C:\work\dev\datakortet>python tstwordlist.py
['DoesNotExist', 'MultipleObjectsReturned', '__class__', '__delattr__', '__dict__', '__doc__', '__eq__', '__format__', '__getattribute__', '__hash__', '__init__', u'__module__', '__ne__', '__new__', '__reduce__', '__reduce_ex__', '__repr__', '__setattr__', '__sizeof__', '__str__', '__subclasshook__', '__weakref__', '_base_manager', '_default_manager', '_deferred', '_get_FIELD_display', '_get_next_or_previous_by_FIELD', '_get_next_or_previous_in_order', '_get_pk_val', '_get_unique_checks', '_meta', '_perform_date_checks', '_perform_unique_checks', '_set_pk_val', '_state', 'clean', 'clean_fields', 'date_error_message', 'delete', 'full_clean', 'length', 'list_id', 'objects', 'pk', 'prepare_database_save', 'save', 'save_base', 'serializable_value', 'title', 'unique_error_message', 'user', 'user_id', 'validate_unique']
0

adding a length2

(dev) C:\work\dev\datakortet>cat maint\models.py
...    
class WordList(models.Model):
    #...

    def length(self):
        return len([])

    def length2(self):
        return len([42])

don’t do a syncdb, but change the program to use length2 (and only print the keys in dir() that start with length)..

(dev) C:\work\dev\datakortet>cat tstwordlist.py
...
wordlists = WordList.objects.filter(user=usr)
for w in wordlists:
    print [name for name in dir(w) if name.startswith('length')]
    print w.length2()

works as expected…

(dev) C:\work\dev\datakortet>python tstwordlist.py
['length', 'length2']
1
👤thebjorn

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