mysql - beego的orm每update,delete,read的时候都要给主键值？？？？

Question

"go
package main

import (
    "fmt"
    "github.com/astaxie/beego/orm"
    _ "github.com/go-sql-driver/mysql"
    "time"
)

type Userinfo struct {
    Uid        int `orm:"pk"`
    Username   string
    Departname string
    Created    time.Time
}

func init() {
    orm.RegisterModel(new(Userinfo))
    orm.RegisterDataBase("default", "mysql", "momaek:123456@/test?charset=utf8")

}

func main() {
    o := orm.NewOrm()
    user := Userinfo{Username: "hello", Departname: "wd"}
    id, err := o.Insert(&user)
    fmt.Printf("ID:%d, Err: %v\n ", id, err)

    user.Uid = 3
    user.Created = time.Now()
    user.Departname = "wakkkk"
    num, err := o.Update(&user)
    fmt.Printf("Num:%d ,ERR: %v\n", num, err)

    u := Userinfo{Username: "hello"}
    err = o.Read(&u)
    fmt.Println(u)
    fmt.Printf("ERR: %v\n", err)

    num, err = o.Delete(&u)
    fmt.Printf("NUM: %d,  Err: %v\n", num, err)

}

"

代码是这样的。然后运行报错：

ID:47, Err: <nil>
Num:0 ,ERR: <nil>
{0 hello  0001-01-01 00:00:00 +0000 UTC}
ERR: missed pk value
NUM: 0,  Err: missed pk value

Answer 1

beego的orm預設應該把id int 當作主鍵

read, update, delete的時候必須有主鍵,應該只有create的時候不需要，因為主鍵是auto的。你主鍵設定是正確的

Uid int `orm:"pk"`

其實建議主鍵是這樣的

Id int

然後這段程式碼，例如read，beego orm 執行的時候，會找到主鍵，取得主鍵的值value，然後執行
select fields from user where uid = value ,你的主鍵的值不存在(0)，orm就沒辦法執行select， 當然會報錯

 u := Userinfo{Username: "hello"}
    err = o.Read(&u)
    fmt.Println(u)
    fmt.Printf("ERR: %v\n", err)

    num, err = o.Delete(&u)
    fmt.Printf("NUM: %d, Err: %v\n", num, err)

Answer 2

http://jinzhu.me/gorm/curd.ht...

感覺這個 orm 比較好用一些。

Answer 3

透過先查詢，找出改主鍵是否有值Read()
Insert Update Delete