gorm关联模型定义注意事项

1.定义belongs to 关联时，如果表主键名不是ID，需要指定主键列，否则预加载查询时不会报错，但查询语句会出

type User struct {
	UserId     int        `gorm:"column:user_id;primaryKey"`
	UserName   string     `gorm:"column:user_name"`
	Company    Company    `gorm:"foreignKey:CompanyId"`
}

type Company struct {
	CompanyId   int    `gorm:"column:company_id;primaryKey"` // 需要指定主键列，否则预加载查询语句会出问题
	CompanyName string `gorm:"column:company_name"`
}

2.定义has one/has many关联时，如果两个表的关联列名对应的字段名称相同，可通过同时定义"references"和"foreignKey"，进行处理，否则预加载查询语句会出错

type User struct {
	UserId     int        `gorm:"column:user_id;primaryKey"`
	UserName   string     `gorm:"column:user_name"`
	Company    Company    `gorm:"foreignKey:CompanyId"`
	CreditCard CreditCard `gorm:"references:UserId;foreignKey:UserId"`  // 同时定义"references"和"foreignKey"
}

type CreditCard struct {
	CreditId int    `gorm:"column:credit_id;primaryKey"`
	CreditNo string `gorm:"column:credit_no"`
	UserId   int    `gorm:"column:user_id"`
}