删除查询受影响的行返回大于0，或者DB中没有记录

this is a piece of code

    public static function delete_ques($ques_id) {
        $con = Connection::get_Connection();
        $sql_delete = "DELETE FROM question WHERE ques_id = " . $ques_id;
        $result_delete = $con->query($sql_delete);
        if ($result_delete->rowCount()) {
            $con->close();
            echo 'hell not ';
            return true;
        } else {
            $con->close();
            echo 'hell yes';
            return false;
        }
    }

i cannot figure it out why its happening

The problem you are facing is because of rowCount(). according to php.net

rowCount() returns the number of rows affected by the last DELETE, INSERT, or UPDATE statement executed by the corresponding PDOStatement object.

In your situation i would use affected_rows. So you if-else code block would be like this

if ($con->affected_rows) {
        $con->close();
        echo 'hell not ';
        return true;
} else {
        $con->close();
        echo 'hell yes';
        return false;
}