修改字段名称 

ALTER TABLE db_name.table_name RENAME COLUMN regionId to region;

修改字段类型

ALTER TABLE db_name.table_name MODIFY COLUMN endTimestamp Int64;

添加字段

ALTER TABEL db_name.table_name ADD COLUMN `$user_id` Nullable(String); 

删除字段

ALTER TABEL db_name.table_name DROP COLUMN `$user_id`;