20 SQL Queries for interview | Complex SQL Queries for Interview

  • 20 SQL Queries for interview :

    In this article I will explain 20 SQL Queries for interview purpose.These are really important queries which will ask in most of the interview questions.

MOST IMPORTANT QUERIES (90% ASKED IN INTERVIEWS)

1.Query to find Second Highest Salary of Employee?(Most important question in 20 SQL Queries for interview)

  • Answer:-

Select distinct Salary from Employee e1 where 2=Select count(distinct Salary) from Employee e2 where e1.salary<=e2.salary;

2.Query to find duplicate rows in table?(click here for explaination)

  • Answer :-

Select * from Employee a where row_id != select max(row_id) for Employee b where a.Employee_num=b.Employee_num;

3.How to fetch  monthly Salary of Employee if annual salary is given?(click here for Explaination)

  • Answer:-

   Select Employee_name,Salary/12 as ‘Monthly Salary’ from employee;

Click here to get information on ROW_ID

4.What is the Query to fetch first record from Employee table?

  • Answer:-

 Select * from Employee where Rownum =1;

Click here to get What is Rownum?

5.What is the Query to fetch last record from the table?

  • Answer:-

Select * from Employee where Rowid= select max(Rowid) from Employee;

20 SQL Queries for interview
Complex SQL Queries

6.What is Query to display first 5 Records from Employee table?

  • Answer:

Select * from Employee where Rownum <= 5;

6.What is Query to display last 5 Records from Employee table?

  • Answer:

Select * from Employee e where rownum <=5

union

select * from (Select * from Employee e order by rowid desc) where rownum <=5;

Click Here to get What is Union?

7.What is Query to display Nth Record from Employee table?

Select * from Employee  where rownum = &n;

DONATE ONLY 5$ TO GET BEST 75 SQL

    INTERVIEW QUESTIONS BOOK


8.How to get 3 Highest salaries records from Employee table?

select distinct salary from employee a where 3 >= (select count(distinct salary) from emp loyee b where a.salary <= b.salary) order by a.salary desc;

9.How to Display Odd rows in Employee table?

Select * from(Select rownum as rno,E.* from Employee E) where Mod(rno,2)=1;

10.How to Display Even rows in Employee table?

Select * from(Select rownum as rno,E.* from Employee) where Mod(rno,2)=0;

11.How to fetch 3rd highest salary using Rank Function?

select * from (Select Dense_Rank() over ( order by  salary desc) as Rnk,E.* from Employee E) where Rnk=3;

Click Here to Get Information on Rank and Dense_Rank

12.How Can i create table with same structure of Employee table?

Create table Employee_1 as Select * from Employee where 1=2;

13.Display first 50% records from Employee table?

Select rownum,E.* from Employee E where rownum<=(Select count(*/2) from Employee);

14.Display last 50% records from Employee table?

Select rownum,E.* from Employee E

minus

Select rownum,E.* from Employee E where rownum<=(Select count(*/2) from Employee);

15.How Can i create table with same structure with data of Employee table?

Create table Employee1 as select * from Employee;

16.How do i fetch only common records between 2 tables.

Select * from Employee;

Intersect

Select * from Employee1;

DONATE ONLY 5$ TO GET BEST 75 SQL

    INTERVIEW QUESTIONS BOOK


CLICK HERE TO GET INFORMATION ABOUT INTERSECT OPERATOR

17.Find Query to get information of Employee where Employee is not assigned to the department.

Select * from Employee where Dept_no Not in(Select Department_no from Employee);

18.How to get distinct records from the table without using distinct keyword.

select * from Employee a where  rowid = (select max(rowid) from Employee b where  a.Employee_no=b.Employee_no);

19.Select all records from Employee table whose name is ‘Amit’ and ‘Pradnya’

Select * from Employee where Name in(‘Amit’,’Pradnya’);

20.Select all records from Employee table where name not in ‘Amit’ and ‘Pradnya’

select * from Employee where name Not  in (‘Amit’,’Pradnya’);

>>>>>>>>>>> Click Here to Get your First ComplexSQL PDF<<<<<<<<<<<<<<<<<<<

HOME

About admin 136 Articles
Oracle Consultant with Vast Experience in Oracle BI and SQL PLSQL Development

4 Comments

5 Trackbacks / Pingbacks

  1. SQL Joins Basic | SQL Joins with Real Life Scenarios | Types of SQL Joins
  2. Data warehousing Concept | OBIEE as Data warehouse | What is Data warehouse? | Data warehouse vs transactional System | Types of Data Warehouse System | OLAP VS OLTP
  3. Database Normalization Examples | Normalization in Database with Examples | Database Normalization with Real Life Examples | Designing Normalized Database
  4. Difference between Truncate and Delete, Drop in SQL | Truncate Delete and Drop Commands in SQL | SQL Difference between Truncate,Delete and Drop Commands | Real Life Examples of Truncate Delete and Drop Command
  5. Interview Questions for HCL | SQL Interview Questions for HCL | Interview Questions Asked in HCL | HCL Interview Questions | 20 Most Important SQL Interview Questions for HCL

Leave a Reply

Your email address will not be published.


*