WordPress多站点主站$post变量为空及查询无结果求助

Hey there, let's work through this WordPress multisite main site content issue — I’ve dealt with similar headaches with directory-based multisites before, so let’s break this down step by step.

First: Rule Out the Obvious #

• Check if your main site actually has content: Log into your main site’s admin (mySite/wp-admin) and head to Posts → All Posts or Pages → All Pages. If there are no published posts/pages here, that’s why your queries are returning empty! If you intended the main site to pull global content, skip to the "Pulling Global Content" section below.
• Verify your Reading Settings: Go to Settings → Reading in the main site admin. Make sure "Your homepage displays" is set to either "Your latest posts" (with published posts existing) or a published page. Choosing a deleted/unpublished page will leave the homepage empty.

Check Multisite Configuration & Query Restrictions #

1. Confirm wp-config.php Multisite Settings #

Double-check your wp-config.php to ensure the main site’s ID is correctly defined (main site should always be BLOG_ID_CURRENT_SITE = 1):

define('WP_ALLOW_MULTISITE', true);
define('MULTISITE', true);
define('SUBDOMAIN_INSTALL', false); // Critical for directory-based multisites
define('DOMAIN_CURRENT_SITE', 'your-domain.com');
define('PATH_CURRENT_SITE', '/');
define('SITE_ID_CURRENT_SITE', 1);
define('BLOG_ID_CURRENT_SITE', 1);

If these values are off, WordPress might be routing queries to the wrong site database tables.

2. Check for Theme/Plugin Query Tampering #

Since all sites share the same theme, it’s possible a custom hook is accidentally restricting the main site’s queries. Look in your theme’s functions.php (or any custom plugins) for hooks like pre_get_posts or posts_where that might target the main site.

For example, this is a common mistake that would blank the main site:

add_action('pre_get_posts', 'restrict_posts_to_subsites');
function restrict_posts_to_subsites($query) {
    if (!is_admin() && $query->is_main_query()) {
        // Oops — this blocks all main site queries
        if (get_current_blog_id() === 1) {
            $query->set('post__in', array(0));
        }
    }
}

If you find code like this, adjust it to either remove the main site restriction or modify it to fit your global content needs.

3. Test for Plugin Conflicts #

Temporarily deactivate all plugins, then check if the main site pulls content. If it works, reactivate plugins one by one to find which one is causing the issue. Some multisite-specific plugins add query restrictions that might accidentally target the main site.

Database Table Checks #

Your main site’s content lives in the wp_posts table (assuming your database prefix is wp_). Log into your database tool (like phpMyAdmin) and:

• Confirm wp_posts has rows with post_status = 'publish' and valid post_type values (e.g., post, page).
• If the table looks empty or corrupted, restore from a backup or use the "Repair Table" option in phpMyAdmin.

Pulling Global Content (Across All Sites) #

If your goal is to show content from your en and de subsites on the main site, the default WP_Query and get_posts() will only pull from the main site’s database table. To fetch content across sites, use switch_to_blog() to iterate through each subsite:

// Get all subsites
$all_sites = get_sites();
$global_content = array();

foreach ($all_sites as $site) {
    // Switch to the subsite
    switch_to_blog($site->blog_id);
    // Fetch posts (adjust args as needed)
    $subsite_posts = get_posts(array(
        'numberposts' => 5,
        'post_status' => 'publish'
    ));
    // Merge into global content array
    $global_content = array_merge($global_content, $subsite_posts);
    // Switch back to main site
    restore_current_blog();
}

// Now you can loop through $global_content to display posts
foreach ($global_content as $post) {
    setup_postdata($post);
    // Display post content (e.g., the_title(), the_content())
}
wp_reset_postdata();

Just make sure to always call restore_current_blog() after switch_to_blog() to avoid breaking subsequent queries.

内容的提问来源于stack exchange，提问作者Gergely Vízvári