mysqli_rollback（$ conn）不起作用

Question

我正在嘗試使用mysql數據庫（InnoDB）在php中測試事務，但是回滾不起作用...

這是我的代碼

<?php 
    $servername = "localhost";
    $username = "root";
    $password = "";
    $database = "test";

    $conn = mysqli_connect($servername, $username, $password, $database);

    mysqli_autocommit($conn, FALSE);    

    mysqli_query($conn,"update person set Balance = 300 where Name = 'Jay'");
    if ($conn->affected_rows > 0) {
        mysqli_commit($conn);
        echo "First Commited <br>";
        mysqli_query($conn,"update person set Balance = 3000 where Name = 'Rv'");       
        if($conn->affected_rows > 0) {
            mysqli_commit($conn);
            echo "Second Commited <br>";
        }else {
            mysqli_rollback($conn);
            echo "First rollback <br>";
        }       
    }   
    mysqli_close($conn);
?>

有什么問題嗎？ （我也在php中嘗試了面向對象的樣式，請從這里參考）

顯示創建表人的查詢結果

Answer 1

您在第二次更新完成之前提交了第一次更新，所以...

mysqli_autocommit($conn, FALSE);    

    mysqli_query($conn,"update person set Balance = 300 where Name = 'Jay'");
    if ($conn->affected_rows > 0) {
        // mysqli_commit($conn); // Remove this line
        // echo "First Commited <br>";
        mysqli_query($conn,"update person set Balance = 3000 where Name = 'Rv'");       
        if($conn->affected_rows > 0) {
            mysqli_commit($conn);
            echo "Second Commited <br>";
        }else {
            mysqli_rollback($conn);
            echo "First rollback <br>";
        }       
    }