现有表Employee，字段：id（int）、firstname（varch

题目类型：[单选] 现有表Employee，字段：id（int）、firstname（varchar）、lastname（varchar）；以下sql语句错误的是()
A、select firstname+’.’+lastnameas’name’from employee
B、select firstname+’.’+lastname=’name’from employee
C、select’name’=firstname+’.’+lastnamefrom employee
D、select firstname，lastname from employee