我需要一个检查主键（字符串）是否已经存在的系统。
如果是，那么我想在第二列中添加1。
如果没有，那么我想添加一个新行，并将第二列的值设置为1。
以下是我的尝试：
$foodWishNameStr = ($_POST["foodWishName"]);
$foodWishPoint = 1;
$sanitized_foodWish = sanitize_text_field($foodWishNameStr); /* Checks for problematic things in the string like invalid UTF-8, it converts < characters to entities, strips all tags, removes line breaks, tabs and extra white space. */
global $wpdb;
//my column names in the table are foodWishName and foodWishPoints:
$sql = "INSERT INTO foodWishes (foodWishName,foodWishPoints) VALUES (%s,%d) ON DUPLICATE KEY UPDATE foodWishPoints + 1 = %d";
// var_dump($sql); // debug
$sql = $wpdb->prepare($sql,$sanitized_foodWish,$foodWishPoint, $foodWishPoint);
// var_dump($sql); // debug
$wpdb->query($sql);
if($sql){ //return the response
echo $sql;
}else{
echo "something went very wrong";
}
exit();
这给了我一个错误：
<div id="error"><p class="wpdberror"><strong>WordPress database error:</strong> [You have an error in your SQL syntax; check the manual that corresponds to your MariaDB server version for the right syntax to use near '+ 1 = 1' at line 1]<br /><code>INSERT INTO foodWishes (foodWishName,foodWishPoints) VALUES ('redwinevinegar',1) ON DUPLICATE KEY UPDATE foodWishPoints + 1 = 1</code></p></div>INSERT INTO foodWishes (foodWishName,foodWishPoints) VALUES (\'redwinevinegar\',1) ON DUPLICATE KEY UPDATE foodWishPoints + 1 = 1
最合适的回答,由SO网友:user44109 整理而成
在我的案例中，这是正确的公式：
$sql = "INSERT INTO foodWishes(foodWishName,foodWishPoints) VALUES (%s,%d) ON DUPLICATE KEY UPDATE foodWishPoints = foodWishPoints +1";
// var_dump($sql); // debug
$sql = $wpdb->prepare($sql,$sanitized_foodWish,$foodWishPoint,);
// var_dump($sql); // debug
$wpdb->query($sql);
if($sql){ //return the response
echo $sql;
}else{
echo "something went very very wrong";
}
exit();
