PHP - MySQL查找行並替換

Question

即時通訊工具試圖弄清楚的是如何在我的MySQL數據庫中找到某些內容，然後替換另一行。例如

mysqli_query($con,"INSERT INTO persons (FirstName, LastName, Age) 
    VALUES ('$_POST[custom]', '$_POST[receiver_email]','$_POST[mc_gross]')"); 

    $result = mysqli_query($con,"SELECT * FROM Persons 
    WHERE FirstName='bjarne'"); 
    mysqli_query($con,"INSERT INTO persons (LastName) 
    VALUES ('$_POST[item_name]')"); 

在這裏，我想它尋找到FirstName是「bjarne」，然後在這種情況下，他與LastName替換'$_POST[item_name]'。

Answer 1

試試這個：

$result = mysqli_query($con,"UPDATE `Persons` SET `LastName`='".$_POST['item_name']."' 
WHERE `FirstName`='bjarne'");