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/*CREATE TABLE Student
(Sno CHAR(9) PRIMARY KEY,
 Sname CHAR(20) UNIQUE,
 Ssex CHAR(2),
 Sage SMALLINT,
 Sdept CHAR(20)
);*/
/*CREATE TABLE Course
(Cno CHAR(4) PRIMARY KEY,
 Cname CHAR(40),
 Cpno CHAR(4),
 Credit SMALLINT,
 FOREIGN KEY (Cpno) REFERENCES Course(Cno)
);*/
/*ALTER TABLE Student ADD S_entrance CHAR;*/
/*ALTER TABLE Student ALTER COLUMN Sage INT;*/
/*ALTER TABLE Course ADD UNIQUE(Cname);*/
/*INSERT
INTO Student (Sno, Sname, Ssex, Sage,Sdept)
VALUES ('200815128', '³Â¶¬', 'ÄÐ', '20', 'IS');*/
/*INSERT
INTO Student (Sno, Sname, Ssex, Sage,Sdept)
VALUES ('200815129', 'Àî·Ò', 'Å®', '20', 'SR');*/
/*INSERT
INTO Student (Sno, Sname, Ssex, Sage,Sdept)
VALUES ('200815130', 'ÑóÑó', 'ÄÐ', '19', 'SR');*/
/*INSERT
INTO Student (Sno, Sname, Ssex, Sage, Sdept)
VALUES ('200815131', 'Î⽨¹ú', 'ÄÐ', '21', 'IS');*/
/*INSERT
INTO Student (Sno, Sname, Ssex, Sage,Sdept)
VALUES ('200815132', '³ÂºÆÄÏ', 'ÄÐ', '20', 'SC');*/
/*INSERT
INTO Student (Sno, Sname, Ssex, Sage, Sdept)
VALUES ('200815133', '´º¶¬', 'Å®', '22', 'SC');*/
UPDATE Student
SET S_entrance = '8'
WHERE S_entrance IS NULL;
SELECT *
from Student