如何在wordpress中插入当前用户名到数据库中

<?php
/*
Plugin Name: Insert Current User to Database
*/

// 声明WordPress插件的激活和停用钩子
register_activation_hook( __FILE__, 'insert_user_data_activation' );
register_deactivation_hook( __FILE__, 'insert_user_data_deactivation' );

// 激活插件时创建数据库表
function insert_user_data_activation() {
    global $wpdb;
    $table_name = $wpdb->prefix . 'user_data';

    $charset_collate = $wpdb->get_charset_collate();

    $sql = "CREATE TABLE $table_name (
        id mediumint(9) NOT NULL AUTO_INCREMENT,
        username varchar(255) NOT NULL,
        PRIMARY KEY  (id)
    ) $charset_collate;";

    require_once( ABSPATH . 'wp-admin/includes/upgrade.php' );
    dbDelta( $sql );
}

// 停用插件时删除数据库表
function insert_user_data_deactivation() {
    global $wpdb;
    $table_name = $wpdb->prefix . 'user_data';
    $wpdb->query( "DROP TABLE IF EXISTS $table_name" );
}

// 在用户登录后插入用户名到数据库
function insert_current_user_to_database() {
    global $wpdb;
    $table_name = $wpdb->prefix . 'user_data';

    $current_user = wp_get_current_user();
    $username = $current_user->user_login;

    $wpdb->insert(
        $table_name,
        array(
            'username' => $username,
        )
    );
}
add_action( 'wp_login', 'insert_current_user_to_database' );