Gorm-嵌套查询

package main

import (
    "fmt"

    "gorm.io/driver/mysql"
    "gorm.io/gorm"
)

type User struct {
    ID       uint
    Name     string
    Email    string
    Password string
    Orders   []Order
}

type Order struct {
    ID         uint
    OrderNo    string
    Amount     float64
    UserID     uint
}

func main() {
    dsn := "user:password@tcp(host:port)/database"
    db, err := gorm.Open(mysql.Open(dsn), &gorm.Config{})
    if err != nil {
        panic(err)
    }
    defer db.Close()

    var users []User
    db.Preload("Orders").Find(&users)

    for _, user := range users {
        fmt.Printf("User: %s\n", user.Name)
        for _, order := range user.Orders {
            fmt.Printf("  Order: %s - %.2f\n", order.OrderNo, order.Amount)
        }
    }
}