我有以下模型,我想更改名称的长度,当我进行迁移时,它没有检测到更改
class Client(db.Model):
__tablename__ = "client"
client_id = db.Column(
db.Integer,
primary_key=True,
autoincrement=True
)
name = db.Column(db.String(65))
email = db.Column(db.String(255))
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例如更改为
name = db.Column(db.String(100))
NFO [alembic.env] No changes in schema detected.
但是当我更改名称时,如果它检测到更改
INFO [alembic.autogenerate.compare] Detected added column 'client.name_test'
INFO [alembic.autogenerate.compare] Detected removed column 'client.name'
Run Code Online (Sandbox Code Playgroud) 我希望我的问题得到理解
例如,我有这个模型
class Area(models.Model):
area_id = models.IntegerField()
name = models.CharField()
last_name = models.CharField()
short_name = models.CharField()
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我想用几个参数进行查询
如果我找不到第一个,那就找第二个,第三个
filter_areas = Area.objects.filter(area_id=3 | name='area_name' | short_name='are')
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喜欢a或者
获取价值并加入 ','
const users = [{
name: "Jon",
age: 34,
country: "ES"
}]
users.map(function(a){
for (let item in a) {
console.log(a[item])
}
})
//users.join(", ");
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我想回来Jon,34,ES.有什么建议?
我是 GraphQL 的相对新手,我正在尝试进行这样的查询
{
user(username: "Jon") {
name
last_lame
username
posts(in_draft : true) {
title
text
in_draft
update_at
}
}
}
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我想过滤用户在草稿中的帖子列表
我可以进行查询的唯一方法是通过模型的关系,但无法过滤草稿中的帖子。一对多
class User(Base):
__tablename__ = 'user'
id = Column(Integer, primary_key=True)
name = Column(String)
last_lame = Column(String)
username = Column(String)
class Post(Base):
__tablename__ = 'post'
id = Column(Integer, primary_key=True)
title = Column(String)
text = Column(String)
in_draft = Column(Boolean)
post_id = Column(Integer, ForeignKey('user.id'))
posts = relationship("User", backref='posts')
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有了这种关系,我用“backref = 'posts'”显示了帖子节点
我的对象:
class User(SQLAlchemyObjectType):
"""User Object."""
class Meta:
model = UserModel …Run Code Online (Sandbox Code Playgroud) 如何通过 id 更新嵌套序列化器中的列表
我的用户有多个联系人
例子:
接触串行器
class ContactSerializer(serializers.ModelSerializer):
class Meta:
model = Contact
fields = [
'id',
'name',
'last_name'
]
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用户序列化器
class UserSerializer(serializers.ModelSerializer):
email = serializers.EmailField(
required=True,
validators=[
UniqueValidator(queryset=User.objects.all())
]
)
contacts = ContactSerializer(many=True)
class Meta:
model = User
fields = [
"email",
"contacts"
]
def update(self, instance, validated_data):
contacts_data = validated_data.pop('contacts')
contacts = (instance.contacts).all()
contacts = list(contacts)
instance.name = validated_data.get('name', instance.name)
instance.save()
# many contacts
for contact_data in contacts_data:
contact = contacts.pop(0)
contact.name = contact_data.get('name', contact.name)
contact.last_name = contact_data.get('last_name', …Run Code Online (Sandbox Code Playgroud) 我有这两门课
class Parent:
def __init__(self, parent_name, parent_age):
self.parent_name = parent_name
self.parent_age = parent_age
class Child(Parent):
def __init__(self, child_name, gender):
self.child_name = child_name
self.gender = gender
super().__init__('Miguel', 29)
c = Child('Kevin', 'Male')
c.parent_name
c.parent_age
c.child_name
c.gender
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我正在尝试实现它 dataclass
如何将父类的属性继承给子类
例如:
@dataclass
class Parent:
parent_name: str
parent_age: int
@dataclass
class Child(Parent):
child_name: str
gender: str
# Inherit here
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