Return value of Gorm complex query

Question

Let's say I have:

type A struct {
  ID   string `gorm:"primary_key"`
  Name string
}

type B struct {
  ID   string `gorm:"primary_key"`
  AId  string
  A    A `gorm:"foreignkey:AId"`
  Val  string
}

If I wanted to do a normal query on A or B, I can just expect the A or B struct back. But if I wanted to do a join, what struct should I expect in go?

For example if my query were:

select * from a join b on a.id = b.a_id;

What does GORM return as a struct?

Answer 1

Converting the query

select * from a join b on a.id = b.a_id;

into gorm:

db.Tables("a").Select("a.id as aid, a.name as aname, b.id as bid, b.a_id as baid, b.val as bval").Joins("JOIN b ON a.id = b.a_id").Find(&result)

We can just create a temporary result struct that houses all fields from both tables a and b.

result := []struct {
    ID   string `db:"aid"`
    Name string `db:"aname"`
    BId  string `db:"bid"`
    AId  string `db:"baid"`
    Val  string `db:"bval"`
}{}

Then, repackage this result struct as needed, or return this struct for the client to use.