PHP+SQL. How to delete an entry from the database?

Question

PHP

There is a simple database with words. The page has a form: input-text "word" and select "dictionary". It is necessary, by clicking on the "delete" button, to delete the word typed by the user, provided that the user has selected a dictionary in which this word exists.
The form data is sent to a php file, where the following code is:

session_start();
require('../connection1.php');
header('Content-Type: text/html; charset=utf8');

if (isset($_POST['word']) && isset($_POST['vocabulary'])){
    $word = $_POST['word'];
    $vocabulary = $_POST['vocabulary'];

    $stmt = $connection->prepare("SELECT `id` FROM `words` WHERE `word` = ?");
    $stmt->bind_param("i", $word);
    $stmt->execute();
    $result1 = $stmt->get_result();
    $row = mysqli_fetch_array($result1);

    $stmt = $connection->prepare("SELECT `id` FROM `words` WHERE `vocabulary` = ?");
    $stmt->bind_param("i", $vocabulary);
    $stmt->execute();
    $result2 = $stmt->get_result();
    $id = mysqli_fetch_array($result2);

    if ($row === $id){
        $query = "DELETE FROM `words` WHERE `words`.`id` = '$row'";
        $result = mysqli_query($connection,$query) or die("Ошибка: ".mysqli_error($connection));

        if($result){
            $_SESSION['smsq'] = "Слово удалено!";
        }else {
            $_SESSION['fsmsq'] = "Ошибка!";
        }
    } else {
        $_SESSION['fsmsq'] = "Ошибка!";
    }
}

header('Location: ../edit-voc.php')

What to fix?)) Newbie + I don’t understand anything in stmt, how many times to use, etc. ...
Or can it be done differently?

Answer 1

Well done for using prepared expressions, but it's too bad not to finish. Prepared expressions must be used for ALL queries involving variables.
Plus, using the $row array in the query does not make the slightest sense.
Also, I'm not sure if word should be bound with type i and not s.
And of course it's all done in one query.

if (isset($_POST['word'], $_POST['vocabulary'])){
    $word = $_POST['word'];
    $vocabulary = $_POST['vocabulary'];

    $query = "DELETE FROM `words` WHERE `word` =? and `vocabulary` = ?";
    $stmt = $connection->prepare($query);
    $stmt->bind_param("ss", $word, $vocabulary);
    $stmt->execute();
    if($stmt->affected_rows){
        $_SESSION['smsq'] = "Слово удалено!";
    } else {
        $_SESSION['fsmsq'] = "Ошибка!";
    }
}
header('Location: ../edit-voc.php');

Separately, I note that you never need to write or die("Ошибка: ".mysqli_error($connection)); u Instead, you need to write once in the file with the connection

mysqli_report(MYSQLI_REPORT_ERROR | MYSQLI_REPORT_STRICT);

and then PHP will report all query errors on its own