mirror of
https://github.com/django/django.git
synced 2024-12-27 11:35:53 +00:00
f7903f7479
running in Oracle. git-svn-id: http://code.djangoproject.com/svn/django/trunk@7826 bcc190cf-cafb-0310-a4f2-bffc1f526a37
61 lines
2.3 KiB
Python
61 lines
2.3 KiB
Python
from django.db import models
|
|
|
|
class Building(models.Model):
|
|
name = models.CharField(max_length=10)
|
|
|
|
def __unicode__(self):
|
|
return u"Building: %s" % self.name
|
|
|
|
class Device(models.Model):
|
|
building = models.ForeignKey('Building')
|
|
name = models.CharField(max_length=10)
|
|
|
|
def __unicode__(self):
|
|
return u"device '%s' in building %s" % (self.name, self.building)
|
|
|
|
class Port(models.Model):
|
|
device = models.ForeignKey('Device')
|
|
port_number = models.CharField(max_length=10)
|
|
|
|
def __unicode__(self):
|
|
return u"%s/%s" % (self.device.name, self.port_number)
|
|
|
|
class Connection(models.Model):
|
|
start = models.ForeignKey(Port, related_name='connection_start',
|
|
unique=True)
|
|
end = models.ForeignKey(Port, related_name='connection_end', unique=True)
|
|
|
|
def __unicode__(self):
|
|
return u"%s to %s" % (self.start, self.end)
|
|
|
|
__test__ = {'API_TESTS': """
|
|
Regression test for bug #7110. When using select_related(), we must query the
|
|
Device and Building tables using two different aliases (each) in order to
|
|
differentiate the start and end Connection fields. The net result is that both
|
|
the "connections = ..." queries here should give the same results.
|
|
|
|
>>> b=Building.objects.create(name='101')
|
|
>>> dev1=Device.objects.create(name="router", building=b)
|
|
>>> dev2=Device.objects.create(name="switch", building=b)
|
|
>>> dev3=Device.objects.create(name="server", building=b)
|
|
>>> port1=Port.objects.create(port_number='4',device=dev1)
|
|
>>> port2=Port.objects.create(port_number='7',device=dev2)
|
|
>>> port3=Port.objects.create(port_number='1',device=dev3)
|
|
>>> c1=Connection.objects.create(start=port1, end=port2)
|
|
>>> c2=Connection.objects.create(start=port2, end=port3)
|
|
|
|
>>> connections=Connection.objects.filter(start__device__building=b, end__device__building=b).order_by('id')
|
|
>>> [(c.id, unicode(c.start), unicode(c.end)) for c in connections]
|
|
[(1, u'router/4', u'switch/7'), (2, u'switch/7', u'server/1')]
|
|
|
|
>>> connections=Connection.objects.filter(start__device__building=b, end__device__building=b).select_related().order_by('id')
|
|
>>> [(c.id, unicode(c.start), unicode(c.end)) for c in connections]
|
|
[(1, u'router/4', u'switch/7'), (2, u'switch/7', u'server/1')]
|
|
|
|
# This final query should only join seven tables (port, device and building
|
|
# twice each, plus connection once).
|
|
>>> connections.query.count_active_tables()
|
|
7
|
|
|
|
"""}
|