Database-Management-System
August 29, 2024Database-Management-System
August 29, 2024Database-Management-System
Question 271
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Consider the following table structures related to a university for Q96 to Q100:-
EMPLOYEE
NAME VARCHAR (30) NOT NULL,
EID VARCHAR (10) NOT NULL,
DEPTNO INT (5) NOT NULL,
HODEID VARCHAR (10),
SALARY INT (10),
PRIMARY KEY (EID),
FOREIGN KEY (HODEID) REFERENCES EMPLOYEE (EID),
FOREIGN KEY (DEPTNO) REFERENCES DEPARTMENT (DID);
DEPARTMENT
DID INT (5) NOT NULL,
DNAME VARCHAR (30) NOT NULL,
HODID VARCHAR (10) NOT NULL,
HODNAME VARCHAR (30),
PRIMARY KEY (DID),
UNIQUE (DANAME),
FOREIGN KEY (HODID) REFERENCES EMPLOYEE (EID);
PROJECT WORK:
EMPID VARCHAR (30) NOT NULL,
PROJNO INT (5) NOT NULL,
PROJECTLOC VARCHAR (30) NOT NULL,
PRIMARY KEY (EMPID, PROJNO),
FOREIGN KEY (EMPID) REFERENCES EMPLOYEE (EID),
Q98: Refer table, structures given above. University decided to give all employees in the ‘SCIENCE’ department a 20% rise in salary. Which of the following query/ queries will compute the above results?
A) UPDATE EMPLOYEE
SET SALARY = SALARY*1.20
WHERE DEPT NO. IN (SELECT DID FROM DEPARTMENT WHERE
DNAME=’SCIENCE’);
B) UPDATE TABLE EMPLOYEE
SET SALARY = SALARY*1.20
WHERE DNAME=’SCIENCE’;
C) ALTER TABLE EMPLOYEE
SET SALARY=SALARY*1.20
WHERE DEPTNO. IN (SELECT DNAME FROM DEPARTMENT WHERE DNAME =’SCIENCE’)
Choose the correct answer from the options given below”
(A) and (B) only
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(A) only
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(B) and (C) only
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(C) only
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-> where deptno in(select did from department where dname=’science’);
Query OK, 3 rows affected
mysql> select * from employee;
![](https://solutionsadda.in/wp-content/uploads/2020/11/Screenshot_51.png)
(B): (The dname column is not there in employee table)
mysql> update employee set salary=salary*1.20
-> where dname=’science’;
ERROR : Unknown column ‘dname’ in ‘where clause’
(C): Alter command is not used for updating values.
-> where deptno in(select did from department where dname=’science’);
Query OK, 3 rows affected
mysql> select * from employee;
![](https://solutionsadda.in/wp-content/uploads/2020/11/Screenshot_51.png)
(B): (The dname column is not there in employee table)
mysql> update employee set salary=salary*1.20
-> where dname=’science’;
ERROR : Unknown column ‘dname’ in ‘where clause’
(C): Alter command is not used for updating values.