现有表Employee,字段:id(int),firstname(varchar),lastname(varchar);以下sql语句正确是哪三项?()
A.selectfirstname+'.'+lastnameas'name'fromemployee
B.selectfirstname+'.'+lastname='name'fromemployee
C.select'name'=firstname+'.'+lastnamefromemployee
D.selectfirstname,lastnamefromemployee
- · 有4位网友选择 B,占比40%
- · 有3位网友选择 D,占比30%
- · 有2位网友选择 A,占比20%
- · 有1位网友选择 C,占比10%