自己写的mysql语句类似如下：
delete from ums_cart uc where uc.p_id = **
报错如下（语法错误）：
You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near ‘uc where uc.u_id =**} and uc.p_id = 2‘ at line 1
解决办法：
delete uc from ums_cart uc where uc.p_id = ** 即可 ，也即在 delete后跟表别名。