A. 正值过敏期间 B. 严重毛细血管扩张 C. 有外伤 D. 老化
A. delete from sales B. delete profits from sales where product_type=’TOYS’ C. delete from sales where product_type=’ToYS’ D. update sales set profits=null where product_type=’TOYS&rsquo
A. 正确 B. 错误