django的model操作汇整详解

yipeiwu_com5年前Python基础

单表操作

增加数据

auther_obj = {"auther_name":"崔皓然","auther_age":1}
models.auther.objects.create(
 **auther_obj
)
models.auther.objects.create(
 auther_name="周雍博",
 auther_age=4
)
obj = models.auther(
 auther_name="崔洪艳",
 auther_age=29
)
obj.save()
obj = models.auther(
 auther_name = "王仙枝",
 auther_age = "50"
)
obj.save()

删除数据

models.auther.objects.filter(auther_name="崔洪艳")[0].delete()

一对多操作

增加数据

a_obj = models.auther.objects.get(id=1)
 
 
models.book.objects.create(
 book_name = "python课程1",
 book_price = 12,
 book_auther = a_obj
)
a_obj = models.auther.objects.get(id=5)
 
models.book.objects.create(
 book_name = "java课程1",
 book_price = 13,
 book_auther_id = a_obj.id
)
a_obj = models.auther.objects.get(id=2)
 
book_dict = {
 "book_name":"python课程2",
 "book_price":14,
 "book_auther_id":a_obj.id
}
 
obj = models.book.objects.create(
 **book_dict
)
a_obj = models.auther.objects.get(id=4)
 
book_dict = {
 "book_name":"java课程2",
 "book_price":15,
 "book_auther":a_obj
}
 
models.book.objects.create(
 **book_dict
)

一对多正向查询

# 查询id为2的书的所有作者的信息
obj = models.book.objects.get(id=2)
 
print(obj.book_auther.auther_name)
print(obj.book_auther.auther_age)
 
obj = models.book.objects.filter(id=2).values("book_name","book_price","book_auther__id","book_auther__auther_name","book_auther__auther_age")
 
print(obj)
# 查询id为2的作者的出版的书
 
obj = models.book.objects.filter(book_auther_id=2).values("book_name","book_price","book_auther__id","book_auther__auther_name","book_auther__auther_age")
print(obj)
 
 
obj = models.book.objects.get(book_auther_id=2)
print(obj.book_auther.auther_age)
print(obj.book_auther.auther_name)
print(obj.book_name)

一对多反向查询

# 查看出版社出版的书
 
obj = models.auther.objects.filter(id=2).values("auther_name","auther_age","book__book_name")
print(obj)
 
obj = models.auther.objects.get(id=2).book_set.values("book_name","book_price","book_auther__id","book_auther__auther_name","book_auther__auther_age")
print(obj)

多对多操作

增加数据

b1 = models.book.objects.get(id=1)
b2 = models.book.objects.get(id=2)
b4 = models.book.objects.get(id=4)
b5 = models.book.objects.get(id=5)
models.publish.objects.get(id=1).publish_book.add(
 b1,b2
)
book_list = [b1,b2]
 
models.publish.objects.get(id=2).publish_book.add(
 *book_list
)

更新数据

book_list = [b1,b2,b4,b5]
models.publish.objects.get(id=1).publish_book.set(book_list)

移除数据

models.publish.objects.get(id=1).publish_book.remove(b1)
 
book_list = [b2, ]
 
models.publish.objects.get(id=1).publish_book.remove(*book_list)  

正向查询

obj = models.publish.objects.get(id=1).publish_book.values("book_name","publish__publish_name")
print(obj)
 
obj = models.publish.objects.filter(id=1).values("publish_name","publish_book__book_name")
print(obj)

反向添加数据

p1 = models.publish.objects.get(id=1)
p2 = models.publish.objects.get(id=2)
p3 = models.publish.objects.get(id=3)
b1.publish_set.add(p1,p2,p3)

反向删除数据

b1.publish_set.remove(p1)

反向更新数据,把remove替换为set就可以了

反向查询

obj = models.book.objects.get(id=1).publish_set.values("publish_name","publish_book__book_name")

model中多表关系和参数 

多对多

一对一

model操作

以上就是本文的全部内容,希望对大家的学习有所帮助,也希望大家多多支持【听图阁-专注于Python设计】。

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