PHP MySQL更新数据

PHP MySQL修改数据

通过PHP函数mysqli_query执行SQL UPDATE语句，可以将数据更新到MySQL表中。下面是将记录更新为test表的简单示例。要更新任何表中的记录，需要使用条件子句查找该记录。下面的示例使用主键来匹配test表中的记录。

请尝试以下示例以了解更新操作。您需要提供id以更新name字段。

<html>

<head>
        <title>更新一条MySQL记录</title>
</head>

<body>
<?php
$dbhost = 'localhost';
$dbuser = 'root';
$dbpass = '123456';

$conn = mysqli_connect($dbhost, $dbuser, $dbpass);

if(! $conn ) {
        die('不能连接: ' . mysqli_error($conn));
}

if(isset($_POST['update'])) {
        $id = $_POST['id'];
        $name = $_POST['name'];

        $sql = "UPDATE test SET name = \"$name\"  WHERE id = $id" ;
        mysqli_select_db($conn,'test');
        $retval = mysqli_query( $conn, $sql );

        if(! $retval ) {
                die('不能更新数据: ' . mysqli_error($conn));
        }
        echo "更新成功<br/>";
        $sql = "SELECT * FROM test WHERE id=$id";
        $query = mysqli_query($conn,$sql);
        $row = mysqli_fetch_array($query);
        echo $row['id'].':::::::::'.$row['name'];
        mysqli_close($conn);
}else {
        ?>
        <form method = "post" action = "<?php echo $_SERVER['PHP_SELF']; ?>">
                <table width = "400" border =" 0" cellspacing = "1"  cellpadding = "2">

                        <tr>
                                <td width = "100"> ID</td>
                                <td><input name = "id" type = "text"  name = "id"></td>
                        </tr>

                        <tr>
                                <td width = "100">Name</td>
                                <td><input name = "name" type = "text" ></td>
                        </tr>

                        <tr>
                                <td width = "100"> </td>
                                <td> </td>
                        </tr>

                        <tr>
                                <td width = "100"> </td>
                                <td>
                                        <input name = "update" type = "submit"   value = "更新数据">
                                </td>
                        </tr>

                </table>
        </form>
        <?php
}
?>

</body>
</html>