Django中的ORM之增

Publish.objects.create("name"="人民出版社",city="北京"}

Publish.objects.create(**{"name":"文艺出版社","city":"上海"}}

book1=Book(title="python",price="88",publish_id="1",publication_date="2017-06-18")

book1.save()

author1=Author(name="jerry")

author1.save()

#获取出版社对象publish_obj=Publish.objects.get(id=4)  

#将出版社的对象绑定到书籍的记录中Book.objects.create(

    title="python",

    price=48.00,

    publication_date="2017-07-12",

    publish=publish_obj,

)

#直接把出版社的id号插入到书籍的记录中Book.objects.create(

    title="python",

    price=48.00,

    publish_id=2,

    publication_date="2017-06-18",

)

author1=Author.objects.get(id=1)#获取id号为1的作者对象

author2=Author.objects.filter(name="tom")#获取名字为"tom"的作者对象

book1=Book.objects.get(id=2)#获取id号为2的书籍对象

book1.authors.add(author1,author2)#为书籍对象添加多个作者对象

book1.authors.add(*[author1,author2])#为书籍对象添加作者对象的列表

book1.authors.remove(*[author1,author2])#删除指定书籍的所有作者

author_obj = Author.objects.filter(name="jerry")#获取名字为"jerry"的作者对象

book_obj=Book.objects.filter(id__gt=3)#获取id大于3的书籍对象集合

author_obj.book_set.add(*book_obj)#为作者对象添加书籍对象集合

author_obj.book_set.remove(*book_obj)#删除指定作者对象所有的书籍

class Book2Author(models.Models):

    author=models.ForeignKey("Author")#为作者指定Author这张表做为外键

    book=models.ForeignKey("Book")#为书籍指定Book这张表做为外键

author_obj=models.Author.objects.filter(id=3)[0]#获取Author表中id为3的作者对象

book_obj=models.Book.objects.filter(id=4)[0]#获取Book表中id为4的书籍对象

obj1=Book2Author.objects.create(author=author_obj,book=book_obj)

obj1.save()

obj2=Book2Author(author=author_obj,book=book_obj)

obj2.save()