使用ORDB的查询语言,分别写出下列查询的SELECT语句;1)检索每个学生的学习课程和成绩。2)检索至少

1) SELECT A. sname B. coursename B. grade FROM student as A A. studies as B;2) SELECT A. sno A. sname FROM student as A A. student as B WHERE A. ciy = B. ciy1) SELECT A. sname, B. coursename, B. grade FROM student as A, A. st