Hexo mysql-orm

1. type Student struct{
       id  int64 
       teacher []*Teacher `orm:"rel(m2m)"`
       father *Father `orm:"rel(fk)"`
       wife *Wife `orm:"rel(one)"`
   }
   type Teacher struct{
       id int64
       student []*Student `orm:"reverse(many)"`
   }
   type Father struct{
       id int64
       student []*Student `orm:"reverse(many)"`
   }
   type Wife struct{
       id int64
       studnet *Student `orm:"reverse(one)"`
   }
2. 一对多 rel(fk) reverse(many)
   一对一 rel(one) reverse(one)
   多对多 rel(m2m) reverse(many)