Question

请参阅我已经检查过旧线程但没有帮助。

这是我的代码，似乎还可以，但会出错：Warning: mysqli_num_rows() expects parameter 1 to be mysqli_result, boolean given

代码：

function getPnr()
{
    $con = mysqli_connect('127.0.0.1', 'root', '', 'safari');
    if (mysqli_connect_errno())
    {
        echo "Failed to connect to MySQL: " . mysqli_connect_error();
        return;
    }
    $pnr = mt_rand(1111111111, 99999999999);                
    $result = mysqli_query($con,"SELECT pnr from tbl_user where pnr = '".$pnr."'");
    if(mysqli_num_rows($result)>0)
        echo "emtpy";//getPnr();
    else
        echo $pnr;
}

这里有什么问题？

更新的代码：

function getPnr()

{

$con = mysqli_connect('127.0.0.1', 'root', '', 'safari');
if (mysqli_connect_errno())
{
    echo "Failed to connect to MySQL: " . mysqli_connect_error();
    return;
}
$pnr = mt_rand(1111111111, 99999999999);                
$result = mysqli_query($con,"SELECT user_pnr from tbl_user where user_pnr = '".$pnr."'") or die(mysqli_error($con);
if(mysqli_num_rows($result)>0)
    echo "emtpy";//getPnr();
else
    echo $pnr;

返回; }

新错误：

Parse error: syntax error, unexpected ';' in F:\wamp\www\safari\REST_APIs_for_RedBus\main.php on line 104

Answer 1

这意味着您的sql查询无法执行。尝试使用您的代码添加错误处理，然后您将获得明确的错误sql消息

 $result = mysqli_query($con,"SELECT pnr from tbl_user where pnr = '".$pnr."'") or die(mysqli_error($con));

检查mysql php中存在的记录

1 个答案: