Как извлечь строку или имя всех внешних ключей, используемых в модели, в датафрейме django-pandas
У меня есть данные, хранящиеся в Django Model/Table, которые я получаю в pandas dataframe через django-pandas (Version: 0.6.6)
Модель имеет 3 столбца в качестве внешнего ключа viz: state_name, district_name and block_name
Модель.py выглядит следующим образом:
####################################################################################
BOOL_CHOICES = ((True, 'Yes'), (False, 'No'))
UNIT_CATEGORIES = (('AMFU', 'AMFU'), ('DAMU', 'DAMU'))
class GroupDetail(models.Model):
"""Village level Whatsapp Information options"""
unit_type = models.CharField(max_length=16, choices=UNIT_CATEGORIES, default="DAMU")
state_name = models.ForeignKey(State, to_field='state_name', on_delete=models.SET_NULL, null=True)
unit_name = models.CharField(max_length=100, default="KVK")
district_name = models.ForeignKey(District, to_field='district_name', on_delete=models.SET_NULL, null=True)
block_name = models.ForeignKey(Block, to_field='block_name', on_delete=models.SET_NULL, null=True)
village_name = models.CharField(max_length=150)
village_covered_through_whatsapp_group = models.BooleanField(verbose_name=_('Village Covered through Whatsapp Group "yes/no"'), choices=BOOL_CHOICES)
number_of_whatsapp_group_created = models.PositiveIntegerField(validators=[MinValueValidator(0), MaxValueValidator(100)])
number_of_farmers_covered_in_the_village = models.PositiveIntegerField(validators=[MinValueValidator(1), MaxValueValidator(1000)])
objects = DataFrameManager()
class Meta:
db_table = 'Group_Info_Table'
constraints = [models.UniqueConstraint(fields=["state_name","district_name", "block_name", "village_name"], name="all_keys_unique_together")]
def __str__(self):
return self.unit_type
return self.state_name
return self.unit_name
return self.district_name
return self.block_name
return self.village_name
return self.village_covered_through_whatsapp_group
return self.number_of_whatsapp_group_created
return self.number_of_farmers_covered_in_the_village
views.py выглядит следующим образом: Случай 1:
Если я получаю данные следующим образом, то возвращается id's всех столбцов, имеющих foreign keys
def amfu_state_wise(request):
state_name_is = None
district_name_is = None
block_name_is = None
if request.method == "POST":
state_name_is=request.POST.get('state')
district_name_is=request.POST.get('district')
block_name_is=request.POST.get('block')
fetch_whole_database = GroupDetail.objects.all()
all_fields = GroupDetail._meta.get_fields()
print("all_fields",all_fields)
fetch_data_df = fetch_whole_database.to_dataframe(['unit_type', 'state_name__id', 'unit_name', 'district_name__id', 'block_name__id', 'village_name', 'village_covered_through_whatsapp_group', 'number_of_whatsapp_group_created', 'number_of_farmers_covered_in_the_village'], index='id')
print("fetch_data_df", fetch_data_df.state_name__id.head(5))
Вывод в консоль выглядит так
all_fields id
31618 11
31619 11
31620 11
31621 11
31622 11
Name: state_name__id, dtype: int64
[15/Jun/2022 12:37:36] "GET /damuwhatsapp/amfu_state_wise HTTP/1.1" 200 16811
Случай 2:
Но когда я фильтрую все объекты модели, он возвращает значение NaN
def amfu_state_wise(request):
state_name_is = None
district_name_is = None
block_name_is = None
if request.method == "POST":
state_name_is=request.POST.get('state')
district_name_is=request.POST.get('district')
block_name_is=request.POST.get('block')
fetch_whole_database = GroupDetail.objects.filter().values().all()
all_fields = GroupDetail._meta.get_fields()
print("all_fields",all_fields)
fetch_data_df = fetch_whole_database.to_dataframe(['unit_type', 'state_name__name', 'unit_name', 'district_name__id', 'block_name__id', 'village_name', 'village_covered_through_whatsapp_group', 'number_of_whatsapp_group_created', 'number_of_farmers_covered_in_the_village'], index='id')
print("fetch_data_df", fetch_data_df.state_name__name.head(5))
Вывод в консоль выглядит так
all_fields id
31618 NaN
31619 NaN
31620 NaN
31621 NaN
31622 NaN
Name: state_name__name, dtype: float64
[15/Jun/2022 12:44:24] "GET /damuwhatsapp/amfu_state_wise HTTP/1.1" 200 16811
Случай 3:
Но когда я использую
fetch_whole_database = GroupDetail.objects.filter.all()
или
fetch_whole_database = GroupDetail.objects.all()
PS: пожалуйста, обратите внимание на строку имени колонки state_name
def amfu_state_wise(request):
state_name_is = None
district_name_is = None
block_name_is = None
if request.method == "POST":
state_name_is=request.POST.get('state')
district_name_is=request.POST.get('district')
block_name_is=request.POST.get('block')
fetch_whole_database = GroupDetail.objects.filter.all()
all_fields = GroupDetail._meta.get_fields()
print("all_fields",all_fields)
fetch_data_df = fetch_whole_database.to_dataframe(['unit_type', 'state_name', 'unit_name', 'district_name__id', 'block_name__id', 'village_name', 'village_covered_through_whatsapp_group', 'number_of_whatsapp_group_created', 'number_of_farmers_covered_in_the_village'], index='id')
print("fetch_data_df", fetch_data_df.state_name.head(5))
Строка внешнего ключа HARYANA возвращается с ошибкой как :
condition = self.build_lookup(lookups, col, value)
File "/home/webtesting/django_venv/lib/python3.9/site-packages/django/db/models/sql/query.py", line 1273, in build_lookup
lookup = lookup_class(lhs, rhs)
File "/home/webtesting/django_venv/lib/python3.9/site-packages/django/db/models/lookups.py", line 27, in __init__
self.rhs = self.get_prep_lookup()
File "/home/webtesting/django_venv/lib/python3.9/site-packages/django/db/models/lookups.py", line 275, in get_prep_lookup
rhs_value = self.lhs.output_field.get_prep_value(rhs_value)
File "/home/webtesting/django_venv/lib/python3.9/site-packages/django/db/models/fields/__init__.py", line 1990, in get_prep_value
raise e.__class__(
ValueError: Field 'id' expected a number but got 'HARYANA'.
[15/Jun/2022 13:18:35] "GET /damuwhatsapp/amfu_state_wise HTTP/1.1" 500 159434
Как получить строку всех колонок с внешними ключами в django-pandas Dataframe?