如果记录不存在，php 不会返回消息 :"Record dont exist"

Question

我制作了一个表单，如果 id“Telefoninumber”存在，该表单将更新表“Komentaar”。但即使我输入不存在的 ID，我仍然得到回显“记录已成功更新”。

<?php
/* Attempt MySQL server connection. Assuming you are running MySQL
server with default setting (user 'root' with no password) */
$link = mysqli_connect("localhost", "root", "", "client.id");

// Check connection
if($link === false){
    die("ERROR: Could not connect. " . mysqli_connect_error());
}

// Attempt update query execution
$sql = "UPDATE clientid SET Komentaar='OK' WHERE          
    Tele foni_number=5207245";

if(mysqli_query($link, $sql)){
    echo "Records were updated successfully.";
} else  {
    echo "ERROR: Could not able to execute $sql. " .             mysqli_error($link);
}

// Close connection
mysqli_close($link);
?>

Answer 1

如果执行查询，您正在打印记录已成功更新。当然，无论是否进行任何更改，查询都会执行。您必须使用 mysqli_affected_rows() 解决您的情况:是否有任何行受到影响。

$sql = "UPDATE clientid SET Komentaar='OK' WHERE Telefoni_number=5207245";
$result = mysqli_query($link, $sql);
if(if (mysqli_affected_rows($link)){
    echo "Records were updated successfully.";
} else  {
    echo "ERROR: Could not able to execute $sql. " . mysqli_error($link);
}