Database-Management-System
August 29, 2024Database-Management-System
August 29, 2024Database-Management-System
Question 267
|
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),
97: On the basis of above given table structures, retrieve the distinct employee ID (EMPID) of all employees of university who are working on project No. 20, 30 and 40.
SELECT EMPID
FROM PROJECTWORK WHERE PROJNO=(20,30,40); |
|
SELECT EMPID
FROM PROJECTWORK WHERE PROJNO IN (20,30,40); |
|
SELECT DISTINCT EMPID
FROM PROJECTWORK WHERE PROJNO IN (20,30,40); |
|
SELECT DISTINCT EMPID
FROM PROJECTWORK WHERE PROJNO=20,30,40; |
mysql> select empid from projectwork where projno=(20,30,40);
ERROR : Operand should contain 1 column(s)
Option (2): (Duplicate empid’s present)
mysql> select empid from projectwork where projno in(20,30,40);
Option (3): (Unique empid’s present)
mysql> select distinct empid from projectwork where projno in(20,30,40);
Option (4): Syntactical error
mysql> select distinct empid from projectwork where projno=20,30,40;
SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near ‘,30,40’ at line 1
mysql> select empid from projectwork where projno=(20,30,40);
ERROR : Operand should contain 1 column(s)
Option (2): (Duplicate empid’s present)
mysql> select empid from projectwork where projno in(20,30,40);
Option (3): (Unique empid’s present)
mysql> select distinct empid from projectwork where projno in(20,30,40);
Option (4): Syntactical error
mysql> select distinct empid from projectwork where projno=20,30,40;
SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near ‘,30,40’ at line 1