Models

Database Settings is in settings.py.

The settings are in a Python dictionary called DATABASES.

To test the database configruation:

1. python manage.py shell

2. > from django.db import connection

3. > cursor = connection.cursor()

No error means configuration is correct.

To define a table:

from django.db import models

class SomeTable(models.Model):

char_field = models.CharField(max_length=20)

web_field = models.URLField()

email_field = models.EmailField(blank=True) # so the field can be blank. The default value is False

many_field = models.ManyToManyField(AnotherTable)

fk_field = models.ForeignKey(MoreTable)

date_field = models.DateField()

def __unicode__(self):

return self.char_field

class Meta: ordering = ['char_field']

• For optional fields, "blank=True" for characters field; "blank=True, null=True" for datetime fields and number fields.
• To show a different labels in the admin interface, use " verbose_name="my label name" " in the field parameter or a string in the first parameter in the field argument. This parameter does not apply to ManyToManyField() or ForeignKey().

To create a row:

p = SomeTable(char_field="", ....)

p.save()

To modify a field:

p.web_field = "...

p.save()

To select all objects:

SomeTable.objects.all()

To select by criteria:

SomeTable.objects.filter(char_field ='some chars')

To select by similar:

SomeTable.objects.filter(char_field__contains="some chars") # double underscores -- LIKE "%some chars%"

try: p = SomeTable.objects.get(char_field='some chars') except SomeTable.DoesNotExist: print "Not in database." else: print "In the database."

To order the output:

SomeTable.objects.order_by("web_field") # ascending

SomeTable.objects.order_by("-web_field") # descending

To update:

SomeTable.objects.all().update(char_field='other chars')

To delete:

SomeTable.objects.filter(char_field='some chars').delete()