I have following two models.
class TeacherInfo(models.Model):
name = models.CharField(max_length=200)
school_id = models.ForeignKey('admin_app.School')
timestamp = models.DateTimeField(auto_now=True, blank=True)
class AssignedSheetStatus(models.Model):
level = models.ForeignKey('admin_app.Levels')
subject = models.ForeignKey('admin_app.Subject')
set = models.ForeignKey('admin_app.Set')
teacher = models.ForeignKey('teacher.TeacherInfo')
assigned_count = models.PositiveIntegerField(default=0)
corrected_count = models.PositiveIntegerField(default=0)
timestamp = models.DateTimeField(auto_now_add=True)
Now I want to join these two tables such that I have name from TeacherInfo and sum of assigned_count , corrected_count.
Normally for one teacher I would do :
AssignedSheetStatus.objects.filter(teacher__id=teacher_id).aggregate(Sum('assigned_count'), Sum('corrected_count'))
But here I want this for all of the teachers in TeacherInfo.
What is the best way to achieve this?
You can do it the other way arround. Annotate over the TeacherInfo:
TeachInfo.objects.annotate(Sum('assignedshetsstatus__assigned_count'), Sum('assignedsheetstatus__corrected_count'))
Related
I have a model Allotment
class Kit(models.Model):
kit_types = (('FLC', 'FLC'), ('FSC', 'FSC'), ('Crate', 'Crate'), ('PP Box', 'PP Box'))
kit_name = models.CharField(max_length=500, default=0)
kit_type = models.CharField(max_length=50, default=0, choices=kit_types, blank=True, null=True)
class AllotmentFlow(models.Model):
flow = models.ForeignKey(Flow, on_delete=models.CASCADE)
kit = models.ForeignKey(Kit, on_delete=models.CASCADE)
asked_quantity = models.IntegerField(default=0)
alloted_quantity = models.IntegerField(default=0)
class Allotment(models.Model):
transaction_no = models.IntegerField(default=0)
dispatch_date = models.DateTimeField(default=datetime.now)
send_from_warehouse = models.ForeignKey(Warehouse, on_delete=models.CASCADE)
flows = models.ManyToManyField(AllotmentFlow)
For a stacked graph I am trying to get the data of different kit_type alloted in different months.
For that I have tried annotate but it isn't getting the desired results
dataset = Allotment.objects.all().annotate(
month=TruncMonth('dispatch_date')).values(
'month').annotate(dcount=Count('flows__kit__kit_type')).values('month', 'dcount')
Expected Output:
[{'month':xyz, 'kit_type':foo, count:123},...]
I am getting the month and count of kit type from above but how do I segregate it by kit_type?
having a field that represents your choice field names in this query is difficult
instead how about use the Count filter argument and annotate to get what you want
dataset = Allotment.objects.all().annotate(month=TruncMonth('dispatch_date')).values('month').annotate(
FLC_count=Count('flows__kit__kit_type', filter=Q(flows__kit__kit_type="FLC")),
FSC_count=Count('flows__kit__kit_type', filter=Q(flows__kit__kit_type="FSC")),
Crate_count=Count('flows__kit__kit_type', filter=Q(flows__kit__kit_type="Crate")),
PP_Box_count=Count('flows__kit__kit_type', filter=Q(flows__kit__kit_type="PP_Box")),
).values('month', 'FLC_count', 'FSC_count', 'Crate_count', 'PP_Box_count')
As the title suggests, I have multiple sets of queries that each return a values list. I then use the values list to filter another queryset. At the moment I can only do this second step one queryset at a time. Is it possible to combine my initial values lists into one super long list? I'm trying to create an activity/news feed like feature.
views.py:
cookie_ids = Cookie.objects.filter(board__pk=self.kwargs['pk']).values_list('id',
flat=True)
sugar_ids = Sugar.objects.filter(board__pk=self.kwargs['pk']).values_list('id',
flat=True)
**then:
context['cookie_actions'] = Action.objects.filter(target_id__in=cookie_ids)
context['sugar_actions'] = Action.objects.filter(target_id__in=sugar_ids)
Edit: I think this is the only model that might matter
Models.py:
class Action(models.Model):
user = models.ForeignKey(User,
related_name='actions',
db_index=True)
verb = models.CharField(max_length=255)
target_ct = models.ForeignKey(ContentType,
blank=True,
null=True,
related_name='target_obj')
target_id = models.PositiveIntegerField(null=True,
blank=True,
db_index=True)
target = GenericForeignKey('target_ct', 'target_id')
created = models.DateTimeField(auto_now_add=True,
db_index=True)
class Meta:
ordering = ('-created',)
You can use chain to combine your querysets
from itertools import chain
cookie_ids = Cookie.objects.filter(board__pk=self.kwargs['pk']).values_list('id',flat=True)
sugar_ids = Sugar.objects.filter(board__pk=self.kwargs['pk']).values_list('id',flat=True)
ids_list = chain(cookie_ids, sugar_ids)
context['total_actions'] = Action.objects.filter(target_id__in=ids_list)
I think this is what you want
cookie_ids=Cookie.objects.filter(board__pk=self.kwargs['pk']).values_list('id',flat=True)
sugar_ids=Sugar.objects.filter(board__pk=self.kwargs['pk']).values_list('id',Ôflat=True)
ids_list = list(cookie_ids) + list(sugar_ids)
context['total_actions'] = Action.objects.filter(target_id__in=ids_list)
Using union
cookie_ids = Cookie.objects.filter(board__pk=self.kwargs['pk']).values_list('id',
flat=True)
sugar_ids = Sugar.objects.filter(board__pk=self.kwargs['pk']).values_list('id',
flat=True)
target_ids = cookie_ids.union(sugar_ids)
My References:
Django QuerySet union link
Django newbie, so if this is super straightfoward I apologize.
I am attempting to get a listing of distinct "Name" values from a listing of "Activity"s for a given "Person".
Models setup as below
class Activity(models.Model):
Visit = models.ForeignKey(Visit)
Person = models.ForeignKey(Person)
Provider = models.ForeignKey(Provider)
ActivityType = models.ForeignKey(ActivityType)
Time_Spent = models.IntegerField(blank=True, null=True)
Repetitions = models.CharField(max_length=20, blank=True, null=True)
Weight_Resistance = models.CharField(max_length=50, blank=True, null=True)
Notes = models.CharField(max_length=500, blank=True, null=True)
class ActivityType(models.Model):
Name = models.CharField(max_length=100)
Activity_Category = models.CharField(max_length=40, choices=Activity_Category_Choices)
Location_Category = models.CharField(max_length=30, blank=True, null=True, choices=Location_Category_Choices)
I can get a listing of all activities done with a given Person
person = Person.objects.get(id=person_id)
activity_list = person.activity_set.all()
I get a list of all activities for that person, no problem.
What I can't sort out is how to generate a list of distinct/unique Activity_Types found in person.activity_set.all()
person.activity_set.values('ActivityType').distinct()
only returns a dictionary with
{'ActivityType':<activitytype.id>}
I can't sort out how to get straight to the name attribute on ActivityType
This is pretty straightforward in plain ol' SQL, so I know my lack of groking the ORM is to blame.
Thanks.
Update: I have this working, sort of, but this CAN'T be the right way(tm) to do this..
distinct_activities = person.activity_set.values('ActivityType').distinct()
uniquelist = []
for x in distinct_activities:
valuetofind = x['ActivityType']
activitytype = ActivityType.objects.get(id=valuetofind)
name = activitytype.Name
uniquelist.append((valuetofind, name))
And then iterate over that uniquelist...
This has to be wrong...
unique_names = ActivityType.objects.filter(
id__in=Activity.objects.filter(person=your_person).values_list('ActivityType__id', flat=True).distinct().values_list('Name', flat=True).distinct()
This should do the trick. There will be not a lot of db hits also.
Writing that down from my phone, so care for typos.
I'm trying to figure out how to execute the following sql join statement in Django without resorting to just raw sql. Is there a way to do it?
Select * from playertable, seasontable where player.id = season.player_id
Here are my models. Just to clarify, I used abbreviated table names in the above query for clarify
class Player(models.Model):
name = models.CharField(max_length=200)
team = models.CharField(max_length=3)
position = models.CharField(max_length=3)
class PlayerSeason(models.Model):
player = models.ForeignKey(Player)
year = models.IntegerField()
games_played = models.IntegerField()
goals = models.IntegerField()
assists = models.IntegerField()
points = models.IntegerField()
plusminus = models.CharField(max_length=200)
pim = models.IntegerField()
ppg = models.IntegerField()
shg = models.IntegerField()
gwg = models.IntegerField()
otg = models.IntegerField()
shots = models.IntegerField()
shooting_percentage = models.DecimalField(max_digits=5, decimal_places=2)
toi = models.CharField(max_length=200)
sftg = models.DecimalField(max_digits=5, decimal_places=2)
face_off = models.DecimalField(max_digits=5, decimal_places=2)
How should I do this with a Django QuerySet?
If all you wanted to do was to get all the players associated with a given season you could make use of Django's backwards relationships
When you use a ForeignKeyField to a model, in this case Season, the that model instances get an attribute which allows you to get a queryset of all the related objects.
In your example you could use season.player_set.all().
You can pass an optional parameter related_name to the ForeignKeyField that allows you to change the name of the season attribute.
Is there a way to do it?
No. Django's ORM deals with one model at a time, and you are getting columns from two tables. Perform a query on either of the models and then access the appropriate field to get the related model.
I'm stuggling to get to grips with relationships in ORM.
I want to get a distinct CostItem queryset related to a particular event.
Normally I'd filter CostFixedList for the particular event I'm interested and get a the Cost_Rate id's. From that I could then get the CostItem id's.
I could do this easily in SQL, but can't understand how to start with ORM. Can anyone point me in the right direction?
class Event(models.Model):
event_type = models.ForeignKey(EventType)
retailer = models.ForeignKey(Retailer)
....
class CostItem(models.Model):
name = models.CharField("Name", max_length=50, unique=True)
cost_type = models.ForeignKey(CostType, verbose_name="Type")
active = models.BooleanField("Active", default=True)
class CostRate(models.Model):
cost_item = models.ForeignKey(CostItem, verbose_name="Item")
valid_from = models.DateField("From")
valid_till = models.DateField("Till")
unit_amount = models.DecimalField("Price Per Unit", max_digits=5, decimal_places=2)
class CostFixedList(models.Model):
event = models.ForeignKey(Event)
cost_rate = models.ForeignKey(CostRate)
units = models.IntegerField()
appointment = models.ForeignKey(Appointment, null=True, blank=True)
I think this should do it (where myevent is the event for which you wish to obtain the CostItem queryset):
qs = CostItem.objects.filter(costrate__costfixedlist__event=myevent)