A.PRIMARY KEY B.CHECK C.DEFAULT D.UNIQUE
(1) (2) (3) (4)
A.SELECT * FROM 课程成绩表 WHERE 成绩>90 AND 课程号 LIKE A% B.SELECT * FROM 课程成绩表 WHERE 成绩>90 OR 课程号 LIKE A% C.SELECT * FROM 课程成绩表 WHERE 成绩>90 AND 课程号 LIKE ‘A%’ D.SELECT * FROM 课程成绩表 WHERE 成绩>90 OR 课程号 LIKE ‘A%’
A.INSERT DATABASE B.BACKUP DATABASE C.RESTORE DATABASE D.UPDATE DATABASE