Server-side email already exist validation in PHP

Question

I have a form and fields are Name, Email, Password. Client-side validation is working perfectly. I am working on server-side validation.

I am getting the issue on else part. For testing, I added echo $email and I am getting the email id. Now that email id will check in the database is exists or not. If exist the display the error if not existing the display the not exist.

if(condition){}
elseif(condition){}
elseif(condition){}
elseif(condition){}
else{
    echo $email; // here I am able to display the email id

    $sql_check_email="SELECT email FROM register WHERE email =?";
    $stmt = $conn->prepare($sql_check_email);
    $stmt->bind_param("s", $email);
    $stmt->execute();
    $stmt->bind_result($email);
    $rows = $stmt->fetch();
    $total_rows = count($rows);
    if( $total_rows > 0 ){
        $_SESSION['email_error']= 'This email is alredy register with us';
        header('location:register');
    }else{
        echo $email;// why my email id not displaying here?
        echo $name;
        echo $password;
        echo $date_of_added;
        echo"Not exist";
    }

It will be good for me if share the reason for downvote so that I will not repeat same in the future — user9437856, May 03 '18 at 18:03
`$email` will be reset to the result of the query, and obviously in the else there was no match found on the database... or you would not be in the else — RiggsFolly, May 03 '18 at 18:08
you didn't store the result, if any. Edit: Consult the duplicates that this was closed with. — Funk Forty Niner, May 03 '18 at 18:22

vp_arth · Accepted Answer · 2018-05-03T18:10:23.633

-1

Your issue is:

$stmt->bind_result($email);

That line replaces variable with query result.
Just use another variable for results.

You also use fetch result wrong, it returns just true/false/null value of fetch state. Use bind_result binded variable to get your results.

edited May 03 '18 at 18:10

answered May 03 '18 at 18:06

vp_arth

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In the else .... there is no email set as obviously it was not found on the database – RiggsFolly May 03 '18 at 18:09
@RiggsFolly, doesn't `bind_param` that work? – vp_arth May 03 '18 at 18:11
1

Yes, that's right. I tried $stmt->bind_result($email_1); and I got my email in else part. @vp_arth, Can you assist me what's wrong in the fetch result? – user9437856 May 03 '18 at 18:13
`$stmt->bind_result($email); $rows = $stmt->fetch();` you bind and fetch the result of your query. If no matching row is found you are binding NOTHING to `$email` – RiggsFolly May 03 '18 at 18:14
See [doc](http://php.net/manual/en/mysqli-stmt.fetch.php). You can use returned value as a flag there was data, but not as fetched dataset. Fetched dataset will be in the `bind_result` variables. – vp_arth May 03 '18 at 18:15
Thanks for the information @vp_arth, and RiggsFolly. Upvote from my side to notice the error. – user9437856 May 03 '18 at 18:22

Server-side email already exist validation in PHP

1 Answers1