Question

查询如下

SELECT `sID` FROM `subscribers` where `Email` LIKE '%xxx@xxx.com%'

和

require_once($_SERVER['DOCUMENT_ROOT'].'/wp-load.php');
$hostname = "dd";
$username = "cc";
$password = "aa";
$dbName = "bb";


$conn = new mysqli($hostname, $username, $password);
if ($conn->connect_error) {
    die("Connection failed: " . $conn->connect_error);
} 
$conn -> select_db("$dbName") or die( "Unable to select database");

check_subscriber($email, $first, $last, $company, $tablename);
function check_subscriber($email, $first, $last, $company, $tablename)
{
    global $wpdb; 
    $emailid=mysql_real_escape_string($email);
    $subscribercheck = "SELECT `sID` FROM `$tablename` where `Email` LIKE '%$emailid%'";
    $subscriber_exists = "";
    $subscriber_exists = $wpdb -> get_results($wpdb->prepare("$subscribercheck",object));
    var_dump($subscriber_exists);

    if(count($subscriber_exists)>0){
        foreach ($subscriber_exists as $subs)
        {
            echo $sid = $subs-> sID;
        }
    }
    else {
        $wpdb -> insert('subscribers', array(
            'First Name' => $first,
            'Last Name' => $last,
            'Company' => $company,
            'Email' => $email,
            'Date' => date("Y-m-d H:i:s"),
        ));
    }
}

var_dump = NULL

我尝试在我们的数据库中运行查询并且它有效，但它似乎没有在这里运行。请帮忙！

定义每个变量。 var_dump = NULL所以它转到"else"条款，其中wpdb -> Insert发生并且有效。

$subscriber_exists = $wpdb -> get_results($wpdb->prepare("$subscribercheck",object));

但是，即使我可以在我们的数据库中运行它，也不会给我任何价值。

Answer 1

以下是我发现的问题：

您正在尝试手动建立数据库连接，而Wordpress已经通过wp-config.php为您设置了此连接。删除用于连接的代码段，并使用$wpdb对象运行查询。
您正在使用$wpdb->prepare()，但未正确设置必要的参数。如果您想使用预准备语句，您需要先了解它们的工作原理read here
因为您没有使用预准备语句，所以在没有它的情况下运行您的常规查询。
确保您的表位于为wordpress设置的同一数据库中。

这就是我重做代码的方式：

function check_subscriber($email, $first, $last, $company, $tablename) {
    global $wpdb;

    $email = $wpdb->esc_like($email);

    $query = "SELECT `sID` FROM `$tablename` where `Email` LIKE '%$email%'";

    $subscribers = $wpdb->get_results($query, object);

    if (count($subscribers) > 0) {
        foreach ($subscribers as $subs) {
            echo $sid = $subs->sID;
        }
    } else {
        $wpdb->insert('subscribers', array(
            'First Name' => $first,
            'Last Name' => $last,
            'Company' => $company,
            'Email' => $email,
            'Date' => date("Y-m-d H:i:s"),
        ));
    }
}

但是，如果您真的想使用预准备语句，请使用：

function check_subscriber($email, $first, $last, $company, $tablename) {
    global $wpdb;

    $query = "SELECT `sID` FROM `$tablename` where `Email` LIKE %s";

    $like_email = '%' . $wpdb->esc_like($email) . '%';

    $subscribers = $wpdb->get_results(
        $wpdb->prepare($query, $like_email),
        object
    );

    if (count($subscribers) > 0) {
        foreach ($subscribers as $subs) {
            echo $sid = $subs->sID;
        }
    } else {
        $wpdb->insert('subscribers', array(
            'First Name' => $first,
            'Last Name' => $last,
            'Company' => $company,
            'Email' => $email,
            'Date' => date("Y-m-d H:i:s"),
        ));
    }
}

无法使用LIKE从Wordpress数据库获取结果

1 个答案: