Given PostgreSQL 9.2.10, Django 1.8, python 2.7.5 and the following models:
class restProdAPI(models.Model):
rest_id = models.PositiveIntegerField(primary_ke
In case you can go with only soapProdAPI's
that contain corresponding restProdAPI
( in terms of your join statement -> linked by host or ip). You can try the following:
soapProdAPI.objects.extra(
select = {
'rest_id' : "app_restProdAPI.rest_id",
'rest_host' : "app_restProdAPI.rest_host",
'rest_ip' : "app_restProdAPI.rest_ip",
'rest_mode' : "app_restProdAPI.rest_mode",
'rest_state': "app_restProdAPI.rest_state"
},
tables = ["app_restProdAPI"],
where = ["app_restProdAPI.rest_host = app_soapProdAPI.soap_host \
OR app_restProdAPI.rest_ip = app_soapProdAPI.soap_ip"]
)
How to filter more?
Since we are using .extra I would advice to read the docs carefully. In general we can't use .filter
with some of the fields inside the select
dict, because they are not part of the soapProdAPI
and Django can't resolve them. We have to stick with the where
kwarg
in .extra
, and since it's a list, we better just add another element.
where = ["app_restProdAPI.rest_host = app_soapProdAPI.soap_host \
OR app_restProdAPI.rest_ip = app_soapProdAPI.soap_ip",
"app_restProdAPI.rest_mode=%s"
],
params = ['Excluded']
If you really need all soapProdAPI's
no matter if they have corresponding restProdAPI
I can only think of a one ugly example where a subquery
is repeated for each field you need.
soapProdAPI.objects.extra(
select = {
'rest_id' : "(select rest_id from app_restProdAPI where app_restProdAPI.rest_host = app_soapProdAPI.soap_host OR app_restProdAPI.rest_ip = app_soapProdAPI.soap_ip)",
'rest_host' : "(select rest_host from app_restProdAPI where app_restProdAPI.rest_host = app_soapProdAPI.soap_host OR app_restProdAPI.rest_ip = app_soapProdAPI.soap_ip)",
'rest_ip' : "(select rest_ip from app_restProdAPI where app_restProdAPI.rest_host = app_soapProdAPI.soap_host OR app_restProdAPI.rest_ip = app_soapProdAPI.soap_ip)",
'rest_mode' : "(select rest_mode from app_restProdAPI where app_restProdAPI.rest_host = app_soapProdAPI.soap_host OR app_restProdAPI.rest_ip = app_soapProdAPI.soap_ip)",
'rest_state': "(select rest_state from app_restProdAPI where app_restProdAPI.rest_host = app_soapProdAPI.soap_host OR app_restProdAPI.rest_ip = app_soapProdAPI.soap_ip)"
},
)