Database Experiment 2: data update

Experiment two Data update experiment guide

（ Data insertion 、 Modification and deletion ）

1． The experiment purpose

（1） For those already built in Experiment 1 student、course、sc Three tables for data insertion 、 Modify and delete operations .

（2） Create view 、 Query view 、 Indexing and so on .

（3） Let students fully understand SQL The flexibility of language , Powerful , experience SQL The reason why language has become the standard of relational database operation language .

2． Experimental content

（1） This experiment is based on Experiment 1 , Insert the data records of the three tables in Experiment 1 、 modify 、 Delete updates , And views 、 Index, etc .

3． The experimental requirements

(1) stay student Enter... In the table 6 Bar record .

INSERT INTO student VALUES('0127',' Chenyuqi ',' male ',21,' Department of accounting ');

INSERT INTO student VALUES('0210',' Shaohuichuang ',' male ',22,' Department of accounting ');

INSERT INTO student VALUES('0229',' Qi Junbao ',' male ',20,' Department of telecommunications ');

INSERT INTO student VALUES('0236',' Zhuxiaoying ',' male ',20,' Department of telecommunications ');

INSERT INTO student VALUES('0240',' Wuruobin ',' male ',20,' Department of accounting ');

INSERT INTO student VALUES('0242','LEO',' male ',21,' Department of foreign languages ');

(2) stay course Enter... In the table 4 Bar record .

INSERT INTO course VALUES('1',' database ',3);

INSERT INTO course VALUES('2',' Internet protocol analysis ',2);

INSERT INTO course VALUES('3','Web defense ',3);

INSERT INTO course VALUES('4','JSP Programming ',3);

(3) stay sc Enter... In the table 10 Bar record , Note that there may be multiple candidates for some courses , There may be no candidates for some courses .

INSERT INTO sc VALUES('0127','1',' database ',97);

INSERT INTO sc VALUES('0229','2',' Internet protocol analysis ',96);

INSERT INTO sc VALUES('0236','3','Web defense ',98);

INSERT INTO sc VALUES('0240','4','JSP Programming ',96);

INSERT INTO sc VALUES('0210','1',' database ',98);

INSERT INTO sc VALUES('0242','3','Web defense ',66);

INSERT INTO sc VALUES('0127','2',' Internet protocol analysis ',93);

INSERT INTO sc VALUES('0127','4','JSP Programming ',92);

INSERT INTO sc VALUES('0229','1',' database ',90);

INSERT INTO sc VALUES('0210','2',' Internet protocol analysis ',99);

(4) Practice deleting and modifying data .

DELETE sc WHERE grade<90;

UPDATE student SET sage=18 WHERE sage=20;

(5) Practice adding multiple records 、 Delete and modify .

DELETE FROM sc WHERE grade BETWEEN 90 AND 93;

INSERT INTO sc VALUES('0242','1',' database ',90),('0240','3','Web defense ',94);

(6) to sc Table indexing , First sno in ascending order 、 Press again cno Descending .

CREATE UNIQUE INDEX scon ON sc(sno ASC,cno DESC);

(7) Delete the above index .

DROP INDEX scon ON sc;

(8) Create view view1, Ask for sno,sname,cname,grade Four fields .

CREATE VIEW view1 AS SELECT sno,cno,cname,grade FROM sc;

(9) Create view view2, Ask for sno,ssex,sage Three fields .

CREATE VIEW view2 AS SELECT sno,ssex,sage FROM student;

Ask to write all the code of Experiment 2 ,
Be careful ：
1. All the code
2. The full width of the code
3. Regular format , Easy to read