我有一个oc_category_description表，其中的列是：

• category_id
• name

和其他表oc_category，其中的列是：

• category_id
• image
• parent_id

在这里，我想显示名称，category_id，image，parent_id，其中oc_category parent_id为0；

这是sql：

的PHP

function getMainCategory()
{
    $stmt = $this->con->prepare("SELECT category_id, image, parent_id, (SELECT oc_category_description.name FROM oc_category_description WHERE oc_category.category_id = oc_category_description.category_id) FROM oc_category WHERE parent_id = 0 ORDER BY category_id ASC");

    $stmt->execute();
    $stmt->bind_result($category_id, $image, $parent_id, $name);

    $users = array();

    while ($stmt->fetch()) {
        $temp = array();
        $temp['category_id'] = $category_id;
        $temp['image'] = $image;
        $temp['parent_id'] = $parent_id;
        $temp['name'] = $name;

        array_push($users, $temp);
    }
    return $users;
}

但它什么也没返回:(