“django.core.exceptions.ValidationError” error

Question

I am writing a simple game in Django, all of things were right, but suddenly..., I was encountered by following error:

• Django.v = 1.7
• Python.v = 3.4

Answer 1

As far as I understand, you already have a database which already has some "Move" entries in it.

If you add a column in a table which already has data in it, you'll need to provide a default value for that column, that the migration will set to all existing entries in the DB for the involved table (otherwise such entries will be invalid, unless null=True is specified as kwarg, if I remember correctly)

Furthermore, it is possible (happens to me ALL THE TIME), that you will need to set, in settings.py, the DATE_INPUT_FORMATS and the DATETIME_INPUT_FORMATS variables, accordingly to your locale and the way you're used to type dates. (See https://docs.djangoproject.com/en/1.7/ref/settings/#date-input-formats)

An example (In Italy, we have DD/MM/YYYY format):

DATE_INPUT_FORMATS = ( "%d/%m/%Y", )
DATETIME_INPUT_FORMATS = ( "%d/%m/%Y %H:%M", )

You django configuration is expecting the following format instead:

 YYYY-MM-DD HH:MM[:ss[.uuuuuu]][TZ]

(Stuff inside the square brackets is optional)

Edit: the auto_now_add kw arg tells that the field value should be set to "now" when adding (and not updating..) an entry