#########################基于对象查询(子查询)############################
按字段（publish）
1) 一对多 ： book -----------------------------------> publish
<----------------------------------
book_set.all()
正向查询按字段：查询python这本书籍的出版社的邮箱
python=models.Book.objects.filter(title="python").first()
print(python.publish.email)
'''
对应sql:
select publish_id from Book where title="python"
select email from Publish where nid = 1
''’
反向查询按 表名小写_set.all() : 苹果出版社出版的书籍名称
publish_obj=models.Publish.objects.filter(name="苹果出版社").first()
for obj in publish_obj.book_set.all():
print(obj.title)
按字段（authors.all()）
2) 多对多： book -------------------------------------> author
<-------------------------------------
book_set.all()
正向查询python作者的年龄：
python = models.Book.objects.filter(title="python").first()
for author in python.authors.all():
print(author.name ,author.age)
反向查询alex出版过的书籍名称：
alex=models.Author.objects.filter(name="alex").first()
for book in alex.book_set.all():
print(book.title)
按字段 authorDetail
3) 一对一 author ----------------------------------------> authordetail
<----------------------------------------
按表名 author(不要_set)
正向查询 alex的手机号：
alex=models.Author.objects.filter(name='alex').first()
print(alex.authorDetail.telephone)
反向查询 家在山东的作者名字：
author_obj =models.AuthorDetail.objects.filter(addr="shandong").first() # shandong只有一个
print(author_obj.author.name)
ad_list=models.AuthorDetail.objects.filter(addr="shandong") # shandong有多个
for ad in ad_list:
print(ad.author.name)
###################基于queryset和__查询（join查询)#####################
查询python这本书籍的出版社的邮箱：
正向查询： 按字段(关联字段)__xxx
ret=models.Book.objects.filter(title="python").values("publish__email")
print(ret.query)
反向查询： 按表名小写__xxx
ret=models.Publish.objects.filter(book__name="python").values("email")
print(ret)
'''SQL：
select publish.email from Book
left join Publish on book.publish_id=publish.nid
where book.title="python"
'''
查询苹果出版社出版的书籍名称：
正向查询：字段__xxxx
ret2=models.Book.objects.filter(publish__name="苹果出版社").values("title")
print("2222222222====>", ret2.query)
反向查询：表名小写__xxx
ret1=models.Publish.objects.filter(name="苹果出版社").values("book__title")
print("111111111====>",ret1.query)
查询alex的手机号
正向查询：字段__xxxx
ret=models.Author.objects.filter(name="alex").values("authorDetail__telephone")
反向查询：表名小写__xxx
models.AuthorDetail.objects.filter(author__name="alex").values("telephone")
查询手机号以151开头的作者出版过的书籍名称以及书籍对应的出版社名称
ret=models.Book.objects.filter(authors__authorDetail__telephone__startswith="151").values('title',"p ublish__name")
print(ret.query)