go - 具有关联的负载模型

Question

我想加载该帖子，并且是作者ID和电子邮件，而不加载其他任何内容。
不需要急于加载，我只需要获取所有帖子并仅包含作者ID和用户名即可
我目前的查询

posts := []interfaces.Post{}
db.Model("User").Find(&posts)

type Post struct{
    gorm.Model
    Title string
    Body string
    UserID uint
    User User
}

type User struct{
    gorm.Model
    Username string
    Email string
    Password string
}

当前 react

        {
            "ID": 1,
            "CreatedAt": "2021-01-09T19:11:42.063274-05:00",
            "UpdatedAt": "2021-01-09T19:11:42.063274-05:00",
            "DeletedAt": null,
            "Title": "What does the fox say",
            "Body": "whawhhwjg",
            "UserID": 1,
            "User": {
                "ID": 1,
                "CreatedAt": "2021-01-09T19:01:28.70267-05:00",
                "UpdatedAt": "2021-01-09T19:01:28.70267-05:00",
                "DeletedAt": null,
                "Username": "12345",
                "Email": "1112@gmail.com",
                "Password": "$2a$04$T1841Dc52MwjSJ2PaPnTwuFASai6zkGw8WFcuQbO1fi9Nug7R3Iqq"
            }
        },

响应我在寻找

 {
            "ID": 1,
            "CreatedAt": "2021-01-09T19:11:42.063274-05:00",
            "UpdatedAt": "2021-01-09T19:11:42.063274-05:00",
            "DeletedAt": null,
            "Title": "What does the fox say",
            "Body": "whawhhwjg",
            "UserID": 1,
            "User": {
                "ID": 1,
                "Username": "12345",
            }
        },

Answer 1

您可以使用Select方法来选择特定字段。

dm.Model("User").Select("ID", "Email", "Username").Find(&posts)

或者，您可以像这样使用 Preload方法。

db.Preload("User", func (db *gorm.DB) *gorm.DB {
  return db.Select("ID", "Email", "Username")
}).
Find(&posts)