postgresql “sql：结果集中没有行”
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"sql: no rows in result set"
提问by 223seneca
I am handling user auth data posted to my Go backend through an HTML form. I am building on some boilerplateto learn Go better.
我正在处理通过 HTML 表单发布到我的 Go 后端的用户身份验证数据。我正在建立一些样板来更好地学习 Go。
My problem is what the following funcreturns:
我的问题是以下func返回的内容：
func (ctrl UserController) Signin(c *gin.Context) {
var signinForm forms.SigninForm
user, err := userModel.Signin(signinForm)
if err := c.ShouldBindWith(&signinForm, binding.Form); err != nil {
c.JSON(406, gin.H{"message": "Invalid signin form", "form": signinForm})
c.Abort()
return
}
if err == nil {
session := sessions.Default(c)
session.Set("user_id", user.ID)
session.Set("user_email", user.Email)
session.Set("user_name", user.Name)
session.Save()
c.JSON(200, gin.H{"message": "User signed in", "user": user})
} else {
c.JSON(406, gin.H{"message": "Invalid signin details", "error": err.Error()})
}
}
The first ifstatement validates the input, and that works fine (error if the email isn't in proper email format, no error if it is). However, if input is properly validated, the elseclause of the second statement is triggered, and the following JSON is returned:
第一个if语句验证输入，并且工作正常（如果电子邮件不是正确的电子邮件格式，则错误，如果是，则没有错误）。但是，如果正确验证输入，else则会触发第二个语句的子句，并返回以下 JSON：
{
error: "sql: no rows in result set",
message: "Invalid signin details"
}
It is probably useful to also post the relevant code in my Usermodel:
在我的User模型中发布相关代码可能也很有用：
//User ...
type User struct {
ID int `db:"id, primarykey, autoincrement" json:"id"`
Email string `db:"email" json:"email"`
Password string `db:"password" json:"-"`
Name string `db:"name" json:"name"`
UpdatedAt int64 `db:"updated_at" json:"updated_at"`
CreatedAt int64 `db:"created_at" json:"created_at"`
}
//UserModel ...
type UserModel struct{}
//Signin ...
func (m UserModel) Signin(form forms.SigninForm) (user User, err error) {
err = db.GetDB().SelectOne(&user, "SELECT id, email, password, name, updated_at, created_at FROM public.user WHERE email=LOWER() LIMIT 1", form.Email)
if err != nil {
return user, err
}
bytePassword := []byte(form.Password)
byteHashedPassword := []byte(user.Password)
err = bcrypt.CompareHashAndPassword(byteHashedPassword, bytePassword)
if err != nil {
return user, errors.New("Invalid password")
}
return user, nil
}
How do I resolve the sql: no rows in result seterror?
如何解决sql: no rows in result set错误？
采纳答案by Pavlo Strokov
You should change the order of operations in your code.
At first you need to get data from request with if err := c.ShouldBindWith(&signinForm, binding.Form); err != nil {and after that you need to try get data from database with user, err := userModel.Signin(signinForm)
您应该更改代码中的操作顺序。首先你需要从请求中获取数据，if err := c.ShouldBindWith(&signinForm, binding.Form); err != nil {然后你需要尝试从数据库中获取数据user, err := userModel.Signin(signinForm)
回答by Onkar Banerjee
There are good reasons for this. Ideally it tries to read paths by the separator, meaning /path/abcd/and /path/abcdare different. abcdIS the resource in the latter while the resource lies somewhere within abcdin the former. With that in mind, then it will not be able to route properly to /path/abcdif you also have a path /pathas well. In order to remove that ambiguity as to which handler to use, you need to mention the handler for the more specific path ie, /path/abcdbefore the more generic one /path.
这有充分的理由。在理想情况下它会尝试通过分离器以读取路径，这意味着/path/abcd/和/path/abcd是不同的。abcd是后者的资源，而资源位于abcd前者的某处。考虑到这一点，/path/abcd如果您也有路径，那么它将无法正确路由到/path。为了消除关于使用哪个处理程序的歧义，您需要提及更具体路径的处理程序，即，/path/abcd在更通用的路径之前/path。
