Question

我有以下Django模型：

class UserProfile(models.Model):
    user = models.ForeignKey(User, unique=True)
    full_name = models.CharField(max_length=100)
    network = models.ForeignKey(Network)
    positions = models.ManyToManyField(Position, through ='Timestamp', blank=True)
    featured_video = models.ForeignKey(VideoInfo, blank=True, null=True)

从SHOW CREATE TABLE userprofile_userprofile，我得到以下MySQL输出：

| userprofile_userprofile | CREATE TABLE `userprofile_userprofile` (
  `id` int(11) NOT NULL AUTO_INCREMENT,
  `user_id` int(11) NOT NULL,
  `full_name` varchar(100) NOT NULL,
  `network_id` int(11) NOT NULL,
  `featured_video_id` int(11) DEFAULT NULL,
  `bio` longtext NOT NULL,
  PRIMARY KEY (`id`),
  UNIQUE KEY `user_id` (`user_id`),
  KEY `userprofile_userprofile_fb2a452b` (`network_id`),
  KEY `userprofile_userprofile_58bbe944` (`featured_video_id`),
  CONSTRAINT `featured_video_id_refs_id_b7c2ab56` FOREIGN KEY (`featured_video_id`) REFERENCES `userprofile_videoinfo` (`id`),
  CONSTRAINT `network_id_refs_id_f5c27879` FOREIGN KEY (`network_id`) REFERENCES `network_network` (`id`),
  CONSTRAINT `user_id_refs_id_da7416c6` FOREIGN KEY (`user_id`) REFERENCES `auth_user` (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=31034 DEFAULT CHARSET=latin1 |

最后七行在这做什么？他们有什么意义？

unique key
key
constraint
engine=InnoDB
auto-increment=31034

Answer 1

键正在创建索引
唯一键是创建一个索引，为所提到的列强制使用唯一值。
constraint ...外键正在创建外键引用，限制只插入已存在的值的值引用的表。
AUTO_INCREMENT 设置起始auto_increment 列值。

了解MySQL CREATE TABLE语法

1 个答案: