大数据计算服务中的客户表customer是一张非分区表，现在想要清空表的内容然后重新上传数据，可以通过将数据清空。
Ainsert overwrite table customer select* from customer;
Btruncate table customer;
Cdelete from customer;
Ddrop table customer;
Ainsert overwrite table customer select* from customer;
Btruncate table customer;
Cdelete from customer;
Ddrop table customer;