_wp_batch_split_terms

WordPress Version: 5.3

/**
 * Splits a batch of shared taxonomy terms.
 *
 * @since 4.3.0
 *
 * @global wpdb $wpdb WordPress database abstraction object.
 */
function _wp_batch_split_terms()
{
    global $wpdb;
    $lock_name = 'term_split.lock';
    // Try to lock.
    $lock_result = $wpdb->query($wpdb->prepare("INSERT IGNORE INTO `{$wpdb->options}` ( `option_name`, `option_value`, `autoload` ) VALUES (%s, %s, 'no') /* LOCK */", $lock_name, time()));
    if (!$lock_result) {
        $lock_result = get_option($lock_name);
        // Bail if we were unable to create a lock, or if the existing lock is still valid.
        if (!$lock_result || $lock_result > time() - HOUR_IN_SECONDS) {
            wp_schedule_single_event(time() + 5 * MINUTE_IN_SECONDS, 'wp_split_shared_term_batch');
            return;
        }
    }
    // Update the lock, as by this point we've definitely got a lock, just need to fire the actions.
    update_option($lock_name, time());
    // Get a list of shared terms (those with more than one associated row in term_taxonomy).
    $shared_terms = $wpdb->get_results("SELECT tt.term_id, t.*, count(*) as term_tt_count FROM {$wpdb->term_taxonomy} tt\n\t\t LEFT JOIN {$wpdb->terms} t ON t.term_id = tt.term_id\n\t\t GROUP BY t.term_id\n\t\t HAVING term_tt_count > 1\n\t\t LIMIT 10");
    // No more terms, we're done here.
    if (!$shared_terms) {
        update_option('finished_splitting_shared_terms', true);
        delete_option($lock_name);
        return;
    }
    // Shared terms found? We'll need to run this script again.
    wp_schedule_single_event(time() + 2 * MINUTE_IN_SECONDS, 'wp_split_shared_term_batch');
    // Rekey shared term array for faster lookups.
    $_shared_terms = array();
    foreach ($shared_terms as $shared_term) {
        $term_id = intval($shared_term->term_id);
        $_shared_terms[$term_id] = $shared_term;
    }
    $shared_terms = $_shared_terms;
    // Get term taxonomy data for all shared terms.
    $shared_term_ids = implode(',', array_keys($shared_terms));
    $shared_tts = $wpdb->get_results("SELECT * FROM {$wpdb->term_taxonomy} WHERE `term_id` IN ({$shared_term_ids})");
    // Split term data recording is slow, so we do it just once, outside the loop.
    $split_term_data = get_option('_split_terms', array());
    $skipped_first_term = array();
    $taxonomies = array();
    foreach ($shared_tts as $shared_tt) {
        $term_id = intval($shared_tt->term_id);
        // Don't split the first tt belonging to a given term_id.
        if (!isset($skipped_first_term[$term_id])) {
            $skipped_first_term[$term_id] = 1;
            continue;
        }
        if (!isset($split_term_data[$term_id])) {
            $split_term_data[$term_id] = array();
        }
        // Keep track of taxonomies whose hierarchies need flushing.
        if (!isset($taxonomies[$shared_tt->taxonomy])) {
            $taxonomies[$shared_tt->taxonomy] = 1;
        }
        // Split the term.
        $split_term_data[$term_id][$shared_tt->taxonomy] = _split_shared_term($shared_terms[$term_id], $shared_tt, false);
    }
    // Rebuild the cached hierarchy for each affected taxonomy.
    foreach (array_keys($taxonomies) as $tax) {
        delete_option("{$tax}_children");
        _get_term_hierarchy($tax);
    }
    update_option('_split_terms', $split_term_data);
    delete_option($lock_name);
}