Django ORM练习题

表结构
# 书
class Book(models.Model):
    title = models.CharField(max_length=32)
    publish_date = models.DateField(auto_now_add=True)
    price = models.DecimalField(max_digits=5, decimal_places=2)
    memo = models.TextField(null=True)
    # 创建外键，关联publish
    publisher = models.ForeignKey(to="Publisher")
    # 创建多对多关联author
    author = models.ManyToManyField(to="Author")

    def __str__(self):
        return "<Book object: {} {}>".format(self.id, self.title)


# 出版社
class Publisher(models.Model):
    name = models.CharField(max_length=32)
    city = models.CharField(max_length=32)

    def __str__(self):
        return "<Publisher object: {} {}>".format(self.id, self.name)


# 作者
class Author(models.Model):
    name = models.CharField(max_length=32)
    age = models.IntegerField()
    phone = models.CharField(max_length=11)

    def __str__(self):
        return "<Author object: {} {}>".format(self.id, self.name)

数据:

-- ----------------------------
-- Records of app01_author
-- ----------------------------
INSERT INTO `app01_author` VALUES ('1', '金老板', '18', '15512351234');
INSERT INTO `app01_author` VALUES ('2', '小哪吒', '20', '15312341234');
INSERT INTO `app01_author` VALUES ('3', 'Alex', '73', '15512341234');

-- ----------------------------
-- Records of app01_publisher
-- ----------------------------
INSERT INTO `app01_publisher` VALUES ('1', '沙河出版社', '北京');
INSERT INTO `app01_publisher` VALUES ('2', '西二旗出版社', '北京');
INSERT INTO `app01_publisher` VALUES ('3', '张江出版社', '上海');
INSERT INTO `app01_publisher` VALUES ('4', '沙河出版社', '上海');

-- ----------------------------
-- Records of app01_book
-- ----------------------------
INSERT INTO `app01_book` VALUES ('1', '跟金老板学开车', '2018-08-03', '12.90', null, '1');
INSERT INTO `app01_book` VALUES ('2', '跟金老板学开潜艇', '2017-08-10', '9.99', null, '1');
INSERT INTO `app01_book` VALUES ('3', '跟老男孩学思想', '2018-09-03', '39.99', null, '2');
INSERT INTO `app01_book` VALUES ('4', '跟egon学喊麦', '2018-06-12', '0.99', null, '4');

-- ----------------------------
-- Records of app01_book_author
-- ----------------------------
INSERT INTO `app01_book_author` VALUES ('3', '1', '1');
INSERT INTO `app01_book_author` VALUES ('4', '1', '2');
INSERT INTO `app01_book_author` VALUES ('5', '2', '1');
INSERT INTO `app01_book_author` VALUES ('2', '2', '2');
INSERT INTO `app01_book_author` VALUES ('6', '3', '3');
INSERT INTO `app01_book_author` VALUES ('7', '4', '3');

练习题
"""
查找所有书名里包含金老板的书
ret = models.Book.objects.filter(title__contains='金老板')
print(ret)

查找出版日期是2018年的书
ret = models.Book.objects.filter(pulishe_date__year=2018)
查找出版日期是2017年的书名
ret = models.Book.objects.filter(publisher_date__year=2017).values('title')
print(ret)
查找价格大于10元的书
ret = models.Book.objects.filter(price__gt=10)
print(ret)
查找价格大于10元的书名和价格
ret = models.Book.objects.filter(price__gt=10).values('title','price')
print(ret)
查找memo字段是空的书
ret = models.Book.objects.filter(Q(memo='')|Q(memo__isnull=True))
print(ret)
查找在北京的出版社
ret = models.Publisher.objects.filter(city='北京')
print(ret)
查找名字以沙河开头的出版社
ret = models.Publisher.objects.filter(name__startwith='沙河').values('name').distinct()
查找“沙河出版社”出版的所有书籍
ret = models.Book.objects.filter(publisher__name=“沙河出版社”)
ret = models.Publisher.objects.filter(name='沙河出版社').values(''book__title')
查找每个出版社出版价格最高的书籍价格
ret = models.Publisher.objects.annotate(max=Max('book__price')).values('name','max')
print(ret)
查找每个出版社的书名以及出的书籍数量
ret =models.Publisher.objects.annotate(count=Count('book')).values('count','name')
查找作者名字里面带“小”字的作者
ret = models.Author.objects.filter(name__contains='小')
print(ret)
查找年龄大于30岁的作者
ret = models.Author.objects.filter(age__gt=30)
print(ret)
查找手机号是155开头的作者
ret = models.Author.objects.filter(phone__startwith='155')
print(ret)
查找手机号是155开头的作者的姓名和年龄
ret = models.Author.objects.filter(phone__startwith=155).values('name','age')
print(ret)
查找每个作者写的价格最高的书籍价格
ret = models.Author.objects.annotate(max_price=Max('book__price')).values('name','max_price' )
print(ret)
查找每个作者的姓名以及出的书籍数量
ret=models.Author.objects.annotate(count=Count('book')).values('name','count')
print(ret)
查找书名是“跟金老板学开车”的书的出版社
ret = models.Book.objects.get(title='跟金老板学开车').publisher
ret = models.Publisher.objects.get(book__title='跟金老板学开车')
print(ret)
查找书名是“跟金老板学开车”的书的出版社所在的城市
ret = models.Book.object.get(name='跟金老板学开车')====
查找书名是“跟金老板学开车”的书的出版社的名称
ret= models.Publisher.objects.filter(book__title=“跟金老板学开车”)
查找书名是“跟金老板学开车”的书的出版社出版的其他书籍的名字和价格
ret = models.Book.objects.filter(publisher=models.Publisher.objects.get(book__title='跟金老板学开车')).exclude(
    title='跟金老板学开车').values('title', 'price')
print(ret)

ret = models.Publisher.objects.get(book__title='跟金老板学开车').book_set.exclude(title='跟金老板学开车').values('title', 'price')
print(ret)
查找书名是“跟金老板学开车”的书的所有作者
ret = models.Author.objects.all(book__title='跟金老板学开车')
查找书名是“跟金老板学开车”的书的作者的年龄
ret = models.Author.objects.filter(book__title=“跟金老板学开车”).values('age'
查找书名是“跟金老板学开车”的书的作者的手机号码
ret = models.Author.objects.filter(book__title=“跟金老板学开车”).values('phone')
查找书名是“跟金老板学开车”的书的作者们的姓名以及出版的所有书籍名称和价钱
ret = models.Author.objects.get(book__title=“跟金老板学开车”).values('name', 'book__title', 'book__price').distinct()
ret = models.Book.objects.get(title='跟金老板学开车').author.values('name','book__title','book__price').distinct

"""