我的一個模型領域如下:Django「DecimalFields必須定義'decimal_places'屬性。」
aaf_1kg_all = models.DecimalField(blank=True, null=True)
當我使用我的模型一般,一切都很好。當我在一個ready()
hook使用它,但是,我得到這個錯誤:
SystemCheckError: System check identified some issues:
ERRORS:
myapp.Model.aaf_1kg_all: (fields.E130) DecimalFields must define a 'decimal_places' attribute.
myapp.Model.aaf_1kg_all: (fields.E132) DecimalFields must define a 'max_digits' attribute.
Django文檔說,這兩個屬性是可選的。我看到了this answer,但在數據庫中定義了小數位數和max_digits。
如果我決定要添加這些屬性,即
aaf_1kg_all = models.DecimalField(blank=True, null=True, max_digits=10, decimal_places=10)
的應用程序運行,但在某些時候我得到這個錯誤,而不是:
Traceback (most recent call last):
[...]
variants.extend(list(sub_qs)) # sub_qs is a QuerySet
File ".../django/db/models/query.py", line 258, in __iter__
self._fetch_all()
File ".../django/db/models/query.py", line 1074, in _fetch_all
self._result_cache = list(self.iterator())
File ".../django/db/models/query.py", line 68, in __iter__
for row in compiler.results_iter(results):
File ".../django/db/models/sql/compiler.py", line 808, in results_iter
row = self.apply_converters(row, converters)
File ".../django/db/models/sql/compiler.py", line 792, in apply_converters
value = converter(value, expression, self.connection, self.query.context)
File ".../django/db/backends/sqlite3/operations.py", line 233, in convert_decimalfield_value
value = expression.output_field.format_number(value)
File ".../django/db/models/fields/__init__.py", line 1608, in format_number
return utils.format_number(value, self.max_digits, self.decimal_places)
File ".../django/db/backends/utils.py", line 200, in format_number
value = value.quantize(decimal.Decimal(".1") ** decimal_places, context=context)
decimal.InvalidOperation: [<class 'decimal.InvalidOperation'>]
我是不是忘了什麼東西?
的'max_digits'和'decimal_places'參數是可選的爲[表單字段](https://docs.djangoproject.com/en/1.9/ref/forms/fields/#decimalfield )。它們是[模型字段]必需的(https://docs.djangoproject.com/en/1.9/ref/models/fields/#decimalfield)。 – Alasdair
這個鏈接http://stackoverflow.com/questions/33827179/python-decimal-invalidoperation-error將幫助你解決你的錯誤 –
我不明白downvotes,但得到一個答案是重要的。感謝人們。 – JulienD