mysqli_fetch_assoc（）期望参数1为mysqli_result，布尔值为

Question

<?php
require_once("connect.php");

$login1 = $_POST['email'];
$password1 = $_POST['password'];
$select = "SELECT id FROM loginregistration WHERE login ='$login1', password   ='$password1'";
$sql = mysqli_query($con,$select);
$row = mysqli_fetch_assoc($sql);
?>`

似乎我的mysqli_query不起作用，我该怎么办？

Answer 1

在查询附近密码中使用AND insted逗号（，），这就是为什么查询返回false并抛出该错误

$select = "SELECT id FROM loginregistration WHERE login ='".$login1."' and password ='".$password1."'";

更新1

如果查询失败，则返回false。所以你可以使用mysqli_error（$ con）;知道错误

    <?php
    require_once("connect.php");

    $login1 = $_POST['email'];
    $password1 = $_POST['password'];
    $select = "SELECT id FROM loginregistration WHERE login ='".$login1."' AND password   ='".$password1."'";
    $sql = mysqli_query($con,$select);

    if($sql === FALSE) { 
        die(mysqli_error($con)); // better error handling
    }

    $row = mysqli_fetch_assoc($sql);
    ?>