1. 打开AMPPS控制面板并停止所有服务。
2. 导航到AMPPS安装目录，通常位于C:\Program Files (x86)\Ampps。
3. 打开文件夹'mysql'-> 'data'，将其中的所有文件移动到'backup'文件夹中。
4. 下载AMPPS v3.9 MySQL回滚脚本并在AMPPS控制面板中打开'Python'。
5. 安装所需的pymysql python包并启动回滚脚本，等待其完成。
6. 重新启动AMPPS控制面板中的所有服务，并尝试连接到数据库。

回滚脚本示例：

from pymysql import connect

mysql_path = 'C:\\Program Files (x86)\\Ampps\\mysql\\bin\\'
mysql_user = 'root'
mysql_password = ''
mysql_port = '3306'
mysql_database = 'mysql'

with connect(host="localhost",
            user=mysql_user,
            password=mysql_password,
            db=mysql_database,
            charset='utf8mb4',
            cursorclass=cursors.DictCursor) as conn:
        with conn.cursor() as cursor:
            try:
                # stop mysql process
                cursor.execute("SET GLOBAL general_log = 'OFF'")
                cursor.execute("set AUTOCOMMIT=0")
                cursor.execute("SET SQL_SAFE_UPDATES = 0")
                cursor.execute("SET FOREIGN_KEY_CHECKS = 0")

                # delete the old tables
                cursor.execute("DROP TABLE IF EXISTS `audit_log`")
                cursor.execute("DROP TABLE IF EXISTS `column_stats`")
                cursor.execute("DROP TABLE IF EXISTS `engine_cost`")

                # add the new tables
                cursor.execute("CREATE TABLE `audit_log` ( `ID` bigint unsigned NOT NULL AUTO_INCREMENT, `EVENT_TIME` datetime(6) NOT NULL, `USER_HOST` varchar(4096) NOT NULL, `THREAD_ID` bigint unsigned NOT NULL, `SERVER_ID` int unsigned NOT NULL, `COMMAND_TYPE` varchar(64) NOT NULL, `ARGUMENTS` blob NOT NULL, PRIMARY KEY (`ID`)) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_0900_ai_ci MYSQL_ROW_FORMAT=DYNAMIC COMMENT='Audit Log Filter'")
                cursor.execute("CREATE TABLE `column_stats` ( `db` varchar(64) NOT NULL, `table_name` varchar(64) NOT NULL, `column_name` varchar(64) NOT NULL, `min_val` blob, `max_val` blob, `null