public static function plugin_activation() { //check version of WP current if (version_compare($GLOBALS['wp_version'], J_CHAT_MINIMUM_VERSION, '<')) { die('Please upgrade your wordpress minium is ' . J_CHAT_MINIMUM_VERSION); } //check version of plugin $plugin_version = get_option('j_chat_version'); if (!$plugin_version) { add_option('j_chat_version', J_CHAT_VERSION); //create table jChatMessage::createTable(); } else { update_option('j_chat_version', J_CHAT_VERSION); } }