django 基本数据操作

Edit

假设在models.py有了这样一个类

from django.db import models
# Create your models here.
from django.db import models
class People(models.Model):
id = models.AutoField(primary_key=True, null=False)
name = models.CharField(max_length=20, null=False)
sex = models.CharField(max_length=16, null=False)
year = models.IntegerField(max_length=16, null=False)
job = models.CharField(max_length=16, null=False)

主要有三个函数filter(), get(),all()

all()

用法最为简单，models.People.objects.all()返回一个可迭代对象，使用事例：

people_list = models.People.objects.all()
for people in people_list:
print(people.id)
print(people.name)
print(people.sex)
print(people.year)
print(people.job)
即可遍历所有的数据

filter()

也是返回一个可迭代对象，models.People.objects.filter(sex='男')可筛选出性别为男的所有人。

get()

返回一个不可迭代对象，models.People.objects.filter(sex='男')如何有多名男性会报错，如果找不到男性也会报错，只能筛选出唯一存在的一个，应该是找主键的，例如

#找id为1的人的所有信息
people = models.People.objects.filter(id='1')
print(people.sex)
print(people.year)

其实这个还有很多的用法，只列举三种了。

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