关联查询

type User struct {
        Id     int64
        Name   string
        Posts  []string
        Orders []string
    }

    type Post struct {
        Id   int64
        Tags []string
    }

    var users []User

    db.Must().Query(`select * from users`).LooseScan(&users, "$..Posts");

    db.Must().Exec(`select`)

    userIds := mapping.Merge(users, func())

    db.Query().LooseScan(batis.LooseDest(&users, "$..Posts","$..Orders")).Error

    db.Query(`select * from posts where user_id in #{userIds}`,
        batis.Param("userIds", userIds)).Link(&users, "user_id <=> $.Id", "$..Posts").Error

    postIds := mapping.Map(users, func())

    db.Query(`select * from tags where post_id in #{postIds}`,
        batis.Param("postIds", postIds)).
        Link(&users, "user_id <=> $.Posts.Id", "$.Post.Tags").Error

    db.Query(`select * from orders where user_id in #{userIds}`,
        batis.Param("userIds", userIds)).
        Link(&users, "user_id <=> $Id", "$.Orders").Error