【Transact-SQL】“一鍵”創建三張表（Student、Course、SC），並插入教材中所有的數據

前面我們提到，教材裏的三張表會反覆用到~

當我們練習“刪除數據”和“修改數據”之後，三張表的內容會變得“面目全非”。

如何快速“復原”，像一切都沒發生過一樣？運行下面的程序就可以啦。

這段代碼難度不大，前面學過“建表”和“插入”語句，現在只是組合在一起了而已。

看不懂的地方，可以在評論區留言。

--Edit by HBU_David @ HeBei University 2020.3.6

DROP TABLE IF EXISTS SC
DROP TABLE IF EXISTS Student
DROP TABLE IF EXISTS Course

CREATE TABLE Student          
 (	
 Sno CHAR(9) PRIMARY KEY,        /* 列級完整性約束條件,Sno是主碼*/                  
 Sname CHAR(20) UNIQUE,          /* Sname取唯一值*/
 Ssex CHAR(2),
 Sage SMALLINT,
 Sdept CHAR(20)
 ); 

CREATE TABLE  Course
 (	
 Cno CHAR(4) PRIMARY KEY,
 Cname CHAR(40),            
 Cpno CHAR(4),               	                      
 Ccredit SMALLINT,
 FOREIGN KEY (Cpno) REFERENCES  Course(Cno) /* 表級完整性約束條件， Cpno是外碼，被參照表是自身*/
 ); 

CREATE TABLE  SC
 (
 Sno CHAR(9), 
 Cno CHAR(4),  
 Grade SMALLINT,
 PRIMARY KEY (Sno,Cno),                      /* 主碼由兩個屬性構成，必須作爲表級完整性進行定義*/
 FOREIGN KEY (Sno) REFERENCES Student(Sno),  /* 表級完整性約束條件，Sno是外碼，被參照表是Student*/
 FOREIGN KEY (Cno)REFERENCES Course(Cno)     /* 表級完整性約束條件，Cno是外碼，被參照表是Course*/
 ); 


INSERT  INTO  Student (Sno,Sname,Ssex,Sdept,Sage) VALUES ('201215121','李勇','男','CS',20);
INSERT  INTO  Student (Sno,Sname,Ssex,Sdept,Sage) VALUES ('201215122','劉晨','女','CS',19);
INSERT  INTO  Student (Sno,Sname,Ssex,Sdept,Sage) VALUES ('201215123','王敏','女','MA',18);
INSERT  INTO  Student (Sno,Sname,Ssex,Sdept,Sage) VALUES ('201215125','張立','男','IS',19);
INSERT  INTO  Student (Sno,Sname,Ssex,Sdept,Sage) VALUES ('201215128','陳冬','男','IS',20);

SELECT * FROM Student

INSERT  INTO Course(Cno,Cname,Cpno,Ccredit)	VALUES ('1','數據庫',NULL,4);
INSERT  INTO Course(Cno,Cname,Cpno,Ccredit)	VALUES ('2','數學',NULL,4);
INSERT  INTO Course(Cno,Cname,Cpno,Ccredit)	VALUES ('3','信息系統',NULL,4);
INSERT  INTO Course(Cno,Cname,Cpno,Ccredit)	VALUES ('4','操作系統',NULL,4);
INSERT  INTO Course(Cno,Cname,Cpno,Ccredit)	VALUES ('5','數據結構',NULL,4);
INSERT  INTO Course(Cno,Cname,Cpno,Ccredit)	VALUES ('6','數據處理',NULL,4);
INSERT  INTO Course(Cno,Cname,Cpno,Ccredit)	VALUES ('7','Pascal語言',NULL,4);

UPDATE Course SET Cpno = '5' WHERE Cno = '1' 
UPDATE Course SET Cpno = '1' WHERE Cno = '3' 
UPDATE Course SET Cpno = '6' WHERE Cno = '4' 
UPDATE Course SET Cpno = '7' WHERE Cno = '5' 
UPDATE Course SET Cpno = '6' WHERE Cno = '7' 

SELECT * FROM Course

INSERT  INTO SC(Sno,Cno,Grade) VALUES ('201215121 ','1',92);
INSERT  INTO SC(Sno,Cno,Grade) VALUES ('201215121 ','2',85);
INSERT  INTO SC(Sno,Cno,Grade) VALUES ('201215121 ','3',88);
INSERT  INTO SC(Sno,Cno,Grade) VALUES ('201215122 ','2',90);
INSERT  INTO SC(Sno,Cno,Grade) VALUES ('201215122 ','3',80);

SELECT * FROM SC

執行後，效果如下圖所示：