SQL 查询语句示例：学生信息、课程和成绩数据库操作

(1) SELECT S#, SNAME FROM S WHERE SEX='男' AND ACE>23; (2) SELECT C# FROM C WHERE C# NOT IN (SELECT C# FROM SC WHERE S#=(SELECT S# FROM S WHERE SNAME='王')); (3) CREATE PROCEDURE getGrade(IN studentNo VARCHAR(10), IN courseNo VARCHAR(10)) BEGIN SELECT GRADE FROM SC WHERE S# = studentNo AND C# = courseNo; END;