Fix the comment counters of WordPress that are stored in MySQL.

fix-wordpress-comment-counter.php

<?php
 
if (!file_exists('../wp-config.php')) {
    die('There doesn\'t seem to be a wp-config.php file. Double check ' .
        'that you updated wp-config-sample.php with the proper database ' .
        'connection information and renamed it to wp-config.php.');
}
 
require('../wp-config.php');
 
$posts_table = $table_prefix . 'posts';
$comments_table = $table_prefix . 'comments';
 
print 'Updating comment counters...<br>';
 
$query = 'SELECT count(comment_id) AS comment_count, comment_post_id ' .
         "FROM $comments_table GROUP BY comment_post_id";
 
$comments = $wpdb->get_results($query);
 
$where = '';
$first = true;
 
if ($comments) {
    foreach ($comments as $comment) {
        $id = $comment->comment_post_id;
        $count = $comment->comment_count;
 
        $query = "UPDATE $posts_table SET comment_count = $count WHERE ID = $id";
        $wpdb->query($query);
 
        if (!$first) {
            $where .= 'AND ';
        }
        $where .= "ID != $id ";
        $first = false;
    }
}
print count($comments) . ' articles has comments.  Their comment ' .
      'counters have been explicitly set.<br />';
 
$query = "UPDATE $posts_table set comment_count = 0 WHERE $where";
$results = $wpdb->get_results($query);
print count($results) . ' comment counters needed to be zeroed of the ' .
      'articles which doesn\'t have any comments.<br />All done!<br />';
 
?>