php - php 中的简单添加？

Question

这个问题已经有答案了:

How to increment value in MySQL with PHP mysqli (4 个回答)

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好吧，所以我想知道是否有一种简单的方法可以在我的代码中使用 Addonetothis 来在运行此代码时添加它的当前 INT + 1 ？

<?php
$server = "localhost";
$user = "**********";
$pass = "**********";
$dbname = "**********";

//Creating connection for mysqli

$conn = new mysqli($server, $user, $pass, $dbname);

//Checking connection

if ($conn->connect_error) {
    die("Connection failed:" . $conn->connect_error);
}

$article_id = $_GET['id'];

if ( ! is_numeric($article_id))
    die("Looks like you are lost!  <a href='#'>Back to Home</a> ");

$sql = "UPDATE Example SET addonetothis='+ 1' WHERE `ID` =$article_id";

if ($conn->query($sql) === TRUE) {
    header("Refresh:1; url=example.php?id=$article_id");
    echo "Thank you!";
} else {
    echo "Error" . $sql . "<br/>" . $conn->error;
}
$conn->close();

Answer 1

所以你会看到...

$sql = "UPDATE Example SET Addonetothis='+ 1' WHERE `ID` =$article_id";

如果在将 Addonetothis 设置为字符串时将其定义为数据库表中的整数，则会崩溃。

您正在寻找的是类似...

$sql = "UPDATE Example SET AddOneToThis = AddOneToThis + 1 WHERE `ID` =$article_id";