选项
A.
SELECT s.sno,sname, grade FROM student s ,score sc WHERE s.sno=sc.sno AND s.smajor='信息管理' AND cname='DB' ;
B.
SELECT s.sno,sname, grade FROM student s,score sc WHERE s.smajor='信息管理' AND cname='DB';
C.
SELECT s.sno,sname, grade FROM student s WHERE smajor='信息管理' AND cname='DB';
D.
SELECT s.sno,sname, grade FROM student s WHERE s.sno=sc.sno AND s.smajor='信息管理' AND cname='DB';
正确答案：A
名词解析
从两表里选数据，From 后应为student s ,score sc；两表关联，所以有s.sno=sc.sno AND；同时条件为检索"信息管理"专业、选修课程DB的学生学号。答案A。