php - 如何使用php/pdo从MySQL数据库中删除友谊并检查其是否成功

我试图从数据库中删除两个用户之间的友谊

友谊表很简单：

friend_one |friend_two
100        |142
142        |100

这是我有的代码，但是不起作用：

if (!empty($_POST)) {

    $remover_id      = $_POST['remover_id'];
    $removed_id      = $_POST['removed_id'];

    try {

        $query = "DELETE * FROM

                 `friendships`

                 WHERE

                 (friend_one = :remover_id AND friend_two = :removed_id)

                 OR

                 (friend_two = :remover_id AND friend_one = :removed_id)

                 ";

        $sth = $connection->prepare($query);

        $sth->execute(
                      array(

                            ':remover_id' => $remover_id,
                            ':removed_id' => $removed_id

                            ));

        if($sth->rowCount () >=0){
            $response["success"] = $http_response_success;
            die(json_encode($response));
            $connection = null;
        } else {
            $response["success"] = $http_response_server_error;
            $response["message"] = $http_message_server_error;
            die(json_encode($response));
            $connection = null;
        }

    } catch (PDOException $ex) {

        $response["success"] = $http_response_server_error;
        $response["message"] = $http_message_server_error;
        die(json_encode($response));
        $connection = null;

    }


} else {
        $response["success"] = $http_response_bad_request;
        $response["message"] = $http_message_bad_request;
        die(json_encode($response));
        $connection = null;
}

首先，我不认为我检查成功的方式是正确的，其次，无论如何，友谊并没有从数据库中删除。

运行此命令时，我会在else语句中发现自己：

    if($sth->rowCount () >=0){
        $response["success"] = $http_response_success;
        die(json_encode($response));
        $connection = null;
    } else {
        $response["success"] = $http_response_server_error;
        $response["message"] = $http_message_server_error;
        die(json_encode($response));
        $connection = null;
    }

最佳答案

您的DELETE语句有一个SQL错误

DELETE FROM `friendships` WHERE
   (friend_one = :remover_id AND friend_two = :removed_id)
   OR
   (friend_two = :remover_id AND friend_one = :removed_id)

delete之后有一个星号，不应有一个星号。 https://dev.mysql.com/doc/refman/5.0/en/delete.html

至于检查PDO错误，则不应使用$sth->rowCount()。

if(!$sth->execute($data)) {
   // Error (SQL Error)
}

if($sth->rowCount() > 0) {
   // At least 1 record was updated / inserted / deleted / (Possibly Selected)
}