如何将MySQL查询转换为GORM查询

go get -u github.com/go-gorm/gorm

import "gorm.io/gorm"

dsn := "user:password@tcp(host:port)/database?charset=utf8mb4&parseTime=True&loc=Local"
db, err := gorm.Open(mysql.Open(dsn), &gorm.Config{})
if err != nil {
    // 处理错误
}

type User struct {
    gorm.Model
    Name  string
    Email string
}

var user User
db.First(&user, 1) // 查询ID为1的用户

var users []User
db.Where("name = ?", "John").Find(&users) // 查询名字为John的用户

type Order struct {
    gorm.Model
    UserID uint
    Amount float64
}

var user User
db.Preload("Orders").First(&user, 1) // 查询ID为1的用户，并预加载关联的订单信息