MySQL按等级查询

--假设使用如下命令创建了一个grade表；

CREATE TABLE grade(
low int(3),
upp INT(3),
grade CHAR(1)

)
INSERT INTO grade VALUES(90,100,'A');
INSERT INTO grade VALUES(80,89,'B');
INSERT INTO grade VALUES(70,79,'C');
INSERT INTO grade VALUES(60,69,'D');
INSERT INTO grade VALUES(50,59,'E');

 

查询所有同同学的sno cno grade列；

SELECT sno,cno,grade FROM score ,grade WHERE degree BETWEEN low AND upp;

+-----+-------+-------+
| sno | cno | grade |
+-----+-------+-------+
| 101 | 3-106 | A |
+-----+-------+-------+
1 row in set