I have Two Models
class Business(models.Model):
BID = models.IntegerField(primary_key=True, default=datetime.now().strftime("%d%y%H%S%m%M%f"))
BusinessName = models.CharField(max_length=150)
ContactPerson = models.CharField(max_length=50)
class BusinessComment(models.Model):
BID = models.ForeignKey(Business, blank=True, null=True)
Rating = models.IntegerField(blank=True, null=True)
Comment = models.TextField(blank=True, null=True)
class BusinessHours(models.Model):
BID = models.ForeignKey(Business, blank=True, null=True)
Day = models.IntegerField(blank=True, null=True)
StartHour = models.CharField(max_length=8, blank=True, null=True)
EndHour = models.CharField(max_length=8, blank=True, null=True)
I want access in single object below values from both models.this concept is left outer join but can I achieve in single object that have all values as below.
BID,BusinessName,ContactPerson,AVG(Rating),Count(Number of Comment) (Condition is Business.BID = BusinessComment.BID)
Business Table Data
BID BusinessName ContactPerson
1 First First
2 Second Second
BusinessHours Table Data
id BID Rating Comment
1 1 3 Comment1
2 1 5 Comment2
3 2 4 Comment3
4 2 5 Comment4
Then result Should be in Object As:
BID Businame ContactPerson Rating Comment
1 First First 4 2
2 Second Second 4.5 2
I have tried many times but I'm Unable to do that.P
EDIT :
today = datetime.datetime.today().weekday() + 1
BusinessHours Table Data
id BID Day Stathours EndHour
145 1 1 12:00am 12:00am
146 1 2 Closed Closed
147 1 3 12:00am 12:00am
148 1 4 Closed Closed
149 1 5 12:00am 12:00am
150 1 6 12:00am 12:00am
151 1 7 12:00am 12:00am
152 2 1 12:00am 12:00am
153 2 2 12:00am 12:00am
154 2 3 12:00am 12:00am
155 2 4 12:00am 12:00am
156 2 5 12:00am 12:00am
157 2 6 12:00am 12:00am
158 2 7 12:00am 12:00am
Now I want to filter data from BusinessHours using filter(BusinessHours.Day = today)
with annotate.So that output will be as below.
BID Businame ContactPerson Rating Comment StartHour EndHours
1 First First 4 2 12:00am 12:00pm
2 Second Second 4.5 2 12:00am 12:00pm
StartHour and EndHour is give value of Current Day.
You can use annotation with aggregation :
from django.db.models import Count, Avg
qs = Business.objcts.annotate(comment_count=Count('businesscomment'),
avg_rating=Avg('businesscomment__rating'))
And, then in the queryset you can access the comment_count
or avg_rating
:
# I am using these fields in values_list for example
qs.values_list('BID', 'BusinessName', 'ContactPerson', 'comment_count', 'avg_rating')
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