Top 130 SQL Interview Questions And Answers

1. Display the dept information from department table.

  Select  *  from  dept;

2. Display the details of all employees

  Select * from emp;

3. Display the name and job for all employees

   Select ename ,job from emp;

4. Display name and salary for all employees.

  Select ename  , sal  from emp;

 

5. Display employee number and total salary  for each employee.

Select empno, sal+comm from emp;

6. Display employee name and annual salary for all employees.

  Select empno,empname,12*sal+nvl(comm,0) annualsal from emp;

7. Display the names of all employees who are working in department number 10

  Select ename from emp where deptno=10;

8. Display the names of all employees working as  clerks and drawing a salary more than 3000

  Select ename from emp where job=’clerk’and sal>3000;

9. Display employee number and names for employees who earn commission

  Select empno,ename from emp where comm is not null and comm>0.

10. Display names of employees who do not earn any commission.

  Select empno ,ename  from emp where comm is  null and comm=0.

11. Display the names of employees who are working as clerk,salesman or analyst and drawing a salary more than 3000.

  Select ename from emp where(job=’clerk’ or job=’salesman’ or job= ‘Analyst’) and sal>3000;

 (Or)

   Select ename from emp wherejob in(‘clerk’,’slaesman’,’analyst’) and sal>3000;

12. Display the names of employees who are working in the company  for the past 5 years.

  Select ename from emp where sysdate-hiredate>5*365;

13. Display the list of employees who have joined the company before 30^th  June 90 after 31^st dec 90.

  Select * from emp where hiredate between ’30-Jun-1990’ and  ’31-dec-1990’;

14. Display current date.

  Select sysdate from dual;

 15. Display the list of users in your  database(using log table).

  Select * from dba_users;

16. Display the names of all tables from the current user.

Select * from tab;

17. Display the name of the Current user.

  Show user;

18. Display the names of employees working in department number 10 or 20 or 40 employees  working  as  clerks,salesman or analyst

Select ename from emp where deptno in(10,20,40) or job in(‘clerks’,’salesman’,’Analyst’);

19. Display the names of employees whose name starts with alphabet S.

Select ename from emp where ename like ‘S%’;

20. Display the names of employees whose name ends with alphabet S.

Select ename from emp where ename like ‘%S’;

21. Display the names of employees whose name have second alphabet A in their names.

Select ename from emp where ename like ‘_S%’;

22. Display the names of employees whose name is exactly five characters in length.

Select ename from emp where length(ename)=5;

(Or)

Select ename from emp where ename like ‘_____’;

23. Display the names of employees who are not working as managers.

 Select * from emp minus(Select * from emp where empno in(Select mgr from emp));

Or

 Select * from emp e where empno not in (Select mgr from emp where mgr is not null);

Or

Select * from emp e where empno not in (Select mgr from emp where e.empno=mgr);

24. Display the names of employees who are not working as SALESMAN or CLERK or 

ANALYST.

Select ename from emp  where job not in(‘clerks’,’salesman’,’Analyst’);

25. Display all rows from Emp table .The System should wait after every screen full of information.

 Set pause on;

26.Display the total number of employees working in the company.

  Select count(*) from emp;

27. Display the total salary being paid to all employees.

  Select sum(sal)+sum(nvl(comm.,0)) form emp;

28. Display the maximum salary from emp table.

Select max(sal ) from emp;

29. Display the minimum salary from emp table.

Select min(sal) from emp;

30. Display the average salary from emp table.

Select avg(sal) from emp;

31. Display the maximum salary being paid to CLERK.

Select max(sal ) from emp  where job=’clerk’;

32. Display the maximum salary being paid in dept no 20.

Select max(sal ) from emp  where deptno=20;

33. Display the min salary being paid to any SALESMAN

Select max(sal ) from emp  where job=’ SALESMAN’;

34. Display the average salary drawn by managers.

Select avg(sal) from emp where job=’MANAGER’;

35. Display the total salary drawn by analyst working in dept no 40.

Select sum(sal)+sum(nvl(comm,0)) from emp where deptno=40;

36. Display the names of employees in order of salary i.e. the name of the employee earning  lowest salary should appear first.

Select ename from emp order by sal;

37.  Display the names of employees in descending order of salary

Select ename from emp order by sal desc;

38. Display the details from emp table in order of emp name.

Select ename from emp order by ename;

39. Display empno,ename,deptno and sal .Sort the output first based on name and within name by deptno  and within deptno by sal;

 Select * from emp order byename,deptno,sal;

40. Display the name of the employee along with their annual salary (sal*12).The name of the employee earning highest annual salary should appear first.

  Select ename,12*(sal+nvl(comm,0)) Annual from emp order by  12*(sal+nvl(comm,0)) desc;

41. Display name ,Sal,hra,pf,da,total sal for each employee.The Output should be in the order of total sal, hra 15% of sal , da 10% of sal , pf 5% of sal total salary will be (sal*hra*da)-pf.

Select ename,sal,sal*15/100 HRA, SAL*5/100 pf,SAL*10/100 da,sal+sal*15/100-sal*5/100 Total_SALARY from emp

42. Display dept numbers and total number of employees within each group.

Select deptno,count(*) from emp group by deptno;

43. Display the various jobs and total number of employees with  each job group.

Select  job,count(*) from emp group by job;

44. Display department numbers and total salary for each department.

Select deptno, sum(sal)  from emp group by deptno;

45. Display department numbers and maximum salary for each department.

Select deptno, max(sal)  from emp group by deptno;

46. Display the various jobs and total salary for each job.

Select  job, sum(sal)  from emp group by job;

47. Display each jobs along  with minimum sal being paid in each job group.

Select  job,min(sal)  from emp group by job;

48.Display the department numbers with more than three employees  in each dept.

Select deptno,count(*) from emp group by deptno having count(*)>3;

49. Display the various jobs along with total sal for each of the jobs where total sal is greater than 40000

Select  job, sum(sal)  from emp group by job having sum(sal)>40000;

50. Display the various jobs along with total number of employee in each job. The output should contain only those jobs with more than three employees.

  Select job,count(*) from emp group by job having count(*)>3.

51. Display the name of emp who earns highest sal.

  Select ename from emp where sal=(select max(sal) from emp);

52. Display the employee number and name of employee working as CLERK and earning highest salary among CLERKS.

  Select empno,ename from emp where job=’CLERK’ and sal=(select max(sal) from emp where job=’CLERK’);

53. Display the name of the salesman who earns a salary more than the highest salary of any clerk.

 Select ename from emp where job=’salesman’ and sal>(select max(sal) from emp where job=’clerk’);

54. Display the names of clerks who earn salary more than that of James of that of sal lesser than that of Scott.

Select ename from emp where job=’clerk’ and sal<(select sal from emp where ename =’scott’) and sal>(select sal from emp where ename=’james’);

55. Display the names of employees who earn a Sal more than that of James or that of salary greater than that of Scott.

  Select ename from emp where sal<(select sal from emp where ename=’Scott’)And sal>(select sal from emp where ename=’James’);

56.  Display the names of employees who earn highest salary in their respective departments.

  Select * from emp e where sal =(select max(sal) form emp where deptno=e.deptno)

57.  Display the names of employees who earn highest salary in their respective job groups.

  Select * from emp e where sal  in(select max(sal) form emp  group by having  e.job=job).

58. Display the employee names who are working in accountings dept.

   Select ename from emp  where deptno=(select deptn0 from dept where dname=’ACCOUNTING’);

(OR)

Select ename from emp  where deptno IN(select deptn0 from dept where dname=’ACCOUNTING’);

59. Display the employee names who are working in CHICAGO.

   Select ename from emp  where deptno=(select deptno from dept where loc=’CHICAGO’);

60. Display the job groups having total salary greater than the maximum salary for managers.

Select job,sum(sal) form emp group by job having sum(sal)>(select max(sal) from emp where job=’MANAGERS’;

61. Display the names of employee from department number 10 with salary greater than that of all employee working in other departments.

  Select ename ,sal ,deptno from emp  e  where deptno=10 and sal>any(select sal from emp where e.deptno!=deptno);

62. Display the name of employees in Uppercase

Select upper(ename) from emp;

63. Display the name of employees in Lower case

Select lower(ename) from emp;

63. Display the name of employees in  Proper case

Select initicap(ename) from emp;

64. Find out the length of your name using appropriate function.

 Select length(‘India’)  from dual;

65. Display the length of all employees names.

 Select sum( length(ename))  from emp;

66. Display the name of the employee concatenate with empno

   Select  ename|| empno from emp;

(or)

Select concat(ename,empno) from emp;

67. Use appropriate function and extract 3 characters staring from 2 characters from the following string ‘Oracle’ i.e the output should be ‘rac’.

  Select substr(‘oracle’,’2’3) from dual;

68.Find the first occurrence of character a from the following string ‘computer maintenance corporation’.

  Select instr(‘computer maintenance corporation’,’a’,1,1) from dual;

69. Replace every occurrence of alphabet A with B in the string Allen’s(user translate function).

Select replace(‘Allens’,’A’,’b’) from dual;

70. Display the information from emp table. Wherever job ‘manager’ is found it should be displayed as boss(replace function).

  Select empno,ename  replace(job,’MANAGER’,’Boss’) JOB from emp;

71. Display empno,ename,deptno from emp table .Instead of display department numbers display the related department name (use decode function).

  Select e.empno ,e.ename ,d.dname from emp e ,dept d where e.deptno=d.deptno;

72. Display your age in days.

  Select round(sysdate-to_date(’15-aug-1947’))from dual;

73. Display your age in months.

Select floor (months_between(sysdate,’15-auf-1947’)) “age in months” from dual;

74. Display current date as 15^th august Friday nineteen forty seven.

Select to_char(sysdate,’date month day year’) from dual;

75.  Display the following output for each row from emp table as ‘scott has joined the company on Wednesday 13^th august nineteen ninety’.

 Select ename || ‘has joined the company on ‘ || to_char (hiredate,’day ddth month ear’) from emp;

76. Find the date of nearest Saturday after Current day.

  Select  next_day (sysdate,’SATURDAY’ ) from dual;

77. Display current time.

 Select to_char(Sysydate,’SATURDAY’) from dual;

78. Display the date three months before the current date.

  Select add_months(sysdate,-3) from dual;

79. Display the common jobs from department number 10 and 20.

Select job from emp where deptno=10 and  job in(select job from emp where deptno=20);

(or)

Select job from emp where deptno=10 intersect select job from emp where deptno=10);

80. Display the jobs found in department number 10 and 20 eliminate duplicate jobs.

  Select distinct(job) from emp where deptno=10 and job in(select job from emp where deptno =20

(or)

Select job from emp where deptno=10 intersect select job from emp where deptno=10);

81. Display the jobs which are unique to dept no 10.

 Select job from emp where deptno=10 minus select job from emp where deptno!=10;

(or)

Select job from emp where deptno=10 and job not in (select job from emp  where deptno<>10);

82. List ename,job, annual sal,deptno,dname and grade who earn 30000 per year and who are not clerks,

select e.ename,e.job, (e.sal+nvl(e.comm,0))*12, e.deptno,d.dname,s.grade from emp e, salgrade s, dept d where e.sal betweem s.lsal  and d.deptno and (e.sal+nvl(cmomm,0))*12> 30000 and e.job<> 'clerk';

83. Find out the jon that was failed in the first half of 1983 and the same job that was failed during the same periond in 1984

Answer me.

84. Find out the all employees who joined the company before thiere manager

select * from emp e where hiredate<(select hiredate from emp where empno=e.mgr);

85. List out the all employees by  name and number along with their manager's name and number also display 'No Manager' who has no manager.

select e.empno,e.ename,m.empno manager,m.ename managername from emp e, emp m where e.mgr=m.empno from emp e, emp m where e,mgr=m.empno union select empno,ename,mgr,'No Manager' from emp where mgr is null;

86 Find out the employees who earned the highest Sal in each job typed sort in descending sal order.

select * from emp e where sal=(select max(sal) from emp where job=e.job);

87.  Find out the employees who earned the min sal for there job in ascending order

select * from emp e where sal=(select min(sal) from emp where job=e.job) order by sal;

88.Find out the most recently hired employees in each dept order by hire date.

select * from emp e where hiredate=(select max(hiredate) from emp where deptno=e.deptno) order by hiredate;

89. Display ename,sal and deptno for each employee who earn a sal greater than the avg of their department order by deptno

select ename,sal,deptno from emp e where sal >(select avg(sal) from emp where deptno=e.deptno) order by deptno;;

90. Display the department where there are no employees;

select deptno,dname from dept where deptno not in(select distinct(deptno) from emp);

91. Display the dept no with highest annual remuneration bill as compensation.

select deptno,sum(sal) from emp group by deptno having sum(sal) = (select mac(sum(sal)) from emp group by deptno);

92. In which year did most people join the company. Display the year and number of employees(hey try out)

Select max(aa) from (select count(*) aa, to _char(hiredate,'yyyy') dd from emp group by to_char(hiredate,'yyyy'))

93. Display avg sal figure for the dept

select deptno,avg(sal) from emp group by deptno;

94. write a query of display against the row of the most recently hired employee. Display ename hire date and column max date showing.

select empno,hiredate from emp where hiredate=(select max (hiredate) from emp);

95. Display employees who can earn more than lowest sal in dept no 30

select * from emp where sal>(select min(sal) from deptno=30);

96. Find employees who can earn more than every employees in dept no 30

select * from emp where sal>(select max(sal) from emp where deptno=30);

select * from emp where sal>all(select sal from emp where deptn0=30);

97. select dept name dept no and sum of sal break on deptno on dname;

select e.deptno,d.dname,sal fdrom emp e, dept d

where e.deptno=d.deptno

order by e.deptno;

98. Find out avg sal and ave total remaninders for each job type

99 . Find all dept's which have more than 3 employees.

select deptno from emp group by deptno having count(*)>3;

100. Display the half of the enames in upper case and remaining lower case.

select concat(upper(substr(ename,0,lengh(ename)/2)), lower (substr(ename,lengh(ename)/2+1,lenght(ename)))) from  emp;

101. select ename if ename exists more than once.

select distinct(ename) from emp e where ename in(select ename from emp where e.empno<>empno);

102. Display all enames in reverse order

select ename from emp order by ename desc;

103. Display those employee whose joining of month and grade is equal.

select empno,ename from emp e,salgrade s where e.sal between s.losal and s.hisal and to_char(hiredate,'mm')=grade;

104. Display those employee whose joining date is available in dept no

select * from emp where to_char(hiredate,'dd')=deptno;

105. Display those employee name as follows A allen, B black

select substr(ename,1,1)||' ' || ename from emp;

106. List out the employees ename,sal pf from emp

select ename,sal,sal*15/100 pf from emp

107. Display RSPS from emp without using updating,inserting

Create table emp with only one column empno

create table emp(empno number(5));

108. Add this column to emp table ename varchar(20)

alter table emp add ename varchar2(20) not null;

109. opps I forgot to give the primary Key constrains. Add it now.

Alter table emp add constrains emp_empno primary key(empno);

110.  now increase the length of ename column to 30 characters,

alter table emp modify ename varchar2(30);

111. Add salary column to emp table.

alter table emp add sal number(7,2);

112. I want to give a validation saying that sal cannot be greater 10,000(note give a name to this comumn)

Alter table emp add constraints emp_sal_check check(sal<10000);

113. For the time begin I have decided that i will not impose this validation. My boss has agreed to pay more than 10,0000

Alter table emp disable constrainsts emp_sal_check;

114. My boss has changed his mind. now he doesn't want to pay more than 10,000. so revoke that salary constraints

Alter table emp enable constraints emp_sal_check;

115. Add column called a s mgr to your emp table.

Alter table emp add mgr number(5);

116. Oh this column should be related to empno. give a command to add this constrains

Alter table emp add constraint emp_mgr foreign key(empno);

117. Add dept no column to your emp table

alter table emp add deptno number(3);

118. This dept no column should be related to deptno column to dept table

alter table emp1 add constraints emp1_deptno foreign key(deptno) referemces dept(deptno);

119. Create table called as new emp. using single command create this table as well as to get data into this table (use create table as)

create table newemp as select * from emp;

120. create table called as newemp. The table should contains only empno,ename,dname

Create table newemp as select empno,ename,dname from emp e, dept d where e,deptno=d.deptno;

121. Delete the rows of employees who are working in the company for more than 3 years

delete from emp where floor(sysdate-hiredaye)>2*365;

122. Provide a commission to employees who are not earning any commission.

update emo set comm=300 where comm is null;

123. If any employees has commsision his commsision should be incremented by 10% of his salary

update emp set comm=comm*10/100 where comm is not null;

124. Display employees name and department name for each employee

select ename,dename from emp e,dept d where e.deptno=d.deptno

125. Display employee number, name and location of the department in which he is working

select empno,ename, loc from emp e, dept d where e.deptno=d.deptno

126.Display ename, dname even if the employees in a particular department(use outer join)

select ename , dname from emp e,dept d where e.deptno(+)=d.deptno;

127. Display employee name and his manager name

select e.ename,m.ename from emp e, emp m where e.mgr=m.empno;

128. Display the department name along with total salary in each department

select deptno,sum(sal) from emp group by deptno;

129.Display the department no and total number of employees in each department

select deptno,count(*) from emp group by deptno;

130. Alter table emp1 add constrains emp1_deptno foreign key(deptno) references dept(deptno)

delete from emp where job name in clerk