云服务器 —— 公有 IP 与 私有 IP

蓝桥杯速成刷题清单（上）

xiaojikeai: CREATE TABLE student ( sno char(9) PRIMARY KEY, sname varchar(20) UNIQUE, ssex char(4) , sage int, sdept varchar(20) ); CREATE TABLE course ( cno char(4) PRIMARY KEY, cname varchar(40) not null, cpno char(4), ccredit smallint CHECK (ccredit=1 OR ccredit=2 OR ccredit=3 OR ccredit=4) ); CREATE TABLE sc ( sno char(9), cno char(4), grade int, PRIMARY KEY(sno,cno), FOREIGN KEY(cno) REFERENCES course(cno), FOREIGN KEY(sno) REFERENCES student(sno) ); INSERT INTO student VALUES ('201215121', '李勇', '男',20,'CS'); INSERT INTO student VALUES ('201215122', '刘晨', '女',19,'CS'); INSERT INTO student VALUES ('201215123', '王敏', '女',18,'MA'); INSERT INTO student VALUES ('201215125', '张立', '男',19,'IS'); INSERT INTO course VALUES ('1', '数据库', '5',4); INSERT INTO course VALUES ('2', '数学', null,2); INSERT INTO course VALUES ('3', '信息系统', '1',4); INSERT INTO course VALUES ('4', '操作系统', '6',3); INSERT INTO course VALUES ('5', '数据结构', '7',4); INSERT INTO course VALUES ('6', '数据处理',null,2); INSERT INTO course VALUES ('7', 'PASCAL语言', '6',4); INSERT INTO sc VALUES ('201215121', '1',92); INSERT INTO sc VALUES ('201215121', '2',85); INSERT INTO sc VALUES ('201215121', '3',88); INSERT INTO sc VALUES ('201215122', '2',90); INSERT INTO sc VALUES ('201215122', '3',80);