delete_transients() - WP

wp-transients.php

/**
 * Deletes all current site transients. (Blog not Network)
 *
 * @return array{ deleted: string[], errored: string[] } An array of successfully and failed to delete transients.
 */
function delete_transients(): array
{
    if (wp_using_ext_object_cache()) {
        global $wp_object_cache;

        $prefix = sprintf(':%d:transient:', get_current_site_id());

        $transients = [];
        foreach ($wp_object_cache->mc['default']->getAllKeys() ?? [] as $transient) {
            if (str_contains($transient, $prefix)) {
                /** @noinspection OffsetOperationsInspection */
                $transients[] = explode($prefix, $transient)[1];
            }
        }
    } else {
        global $wpdb;

        $transients = $wpdb->get_col("SELECT option_name FROM $wpdb->options WHERE option_name LIKE '_transient_%'");

        $transients = array_map(static fn($key) => str_replace('_transient_', '', $key), $transients);
    }

    $deleted = [];
    $errored = [];
    foreach ($transients as $transient) {
        if (delete_transient($transient)) {
            $deleted[] = $transient;
        } else {
            $errored[] = $transient;
        }
    }

    return ['deleted' => $deleted, 'errored' => $errored];
}