EDUCBA

EDUCBA

MENUMENU
  • Free Tutorials
  • Free Courses
  • Certification Courses
  • 360+ Courses All in One Bundle
  • Login
Home Data Science Data Science Tutorials SQL Tutorial SQL Interview Questions
Secondary Sidebar
SQL Tutorial
  • Interview Questions
    • SQL Interview Questions
    • Advance SQL Interview Questions
    • SQL Joins Interview Questions
    • SQL Server Interview Questions
    • SQL Current Month
  • Basic
    • What is SQL
    • Careers in SQL
    • Careers in SQL Server
    • IS SQL Microsoft?
    • SQL Management Tools
    • What is SQL Developer
    • Uses of SQL
    • How to Install SQL Server
    • What is SQL Server
    • SQL Quick References
    • SQL Like Wildcard
    • SQL Like with Multiple Values
    • SQL Examples
    • SQL Server Versions
    • SQL DROP DB
    • SQL Case Insensitive
    • SQL Expressions
    • Database in SQL
    • SQL Data Types
    • SQL Keywords
    • Composite Key in SQL
    • SQL WAITFOR
    • SQL Constraints
    • Transactions in SQL
    • First Normal Form
    • SQL Server Data Types
    • SQL Administration
    • SQL Variables
    • SQL Enum
    • SQL GROUP BY WHERE
    • SQL ROW
    • SQL EXECUTE
    • SQL EXCLUDE
    • SQL Performance Tuning
    • SQL UUID
    • Begin SQL
    • SQL Update Join
    • SQL Between Dates
    • Cheat sheet SQL
  • Operators
    • SQL Operators
    • SQL Arithmetic Operators
    • SQL Logical Operators
    • SQL String Operators
    • Ternary Operator in SQL
  • Commands
    • SQL Commands
    • sqlplus set commands
    • SQL Alter Command
    • SQL Commands Update
    • SQL DML Commands
    • SQL DDL Commands
    • FETCH in SQL
  • Clause
    • SQL Clauses
    • SQL IN Operator
    • SQL SELECT DISTINCT Multiple Columns
    • SQL Null Values
    • SQL LIKE
    • SQL LIKE Query
    • SQL LIKE Operator
    • SQL LIKE Clause
    • SQL NOT Operator
    • SQL Minus
    • SQL WHERE Clause
    • SQL with Clause
    • SQL HAVING Clause
    • SQL HAVING Clause
    • SQL GROUP BY DAY
    • ORDER BY Clause in SQL
    • SQL ORDER BY CASE
    • SQL ORDER BY DESC
    • SQL ORDER BY DATE
    • SQL ORDER BY Alphabetical
    • SQL ORDER BY Ascending
    • SQL Order by Count
    • SQL GROUP BY Month
    • SQL GROUP BY Multiple Columns
    • SQL GROUPING SETS
  • Queries
    • SQL Insert Query
    • SQL SELECT Query
    • SQL SELECT RANDOM
    • SQL Except Select
    • SQL Subquery
    • SQL SELECT DISTINCT
    • SQL WITH AS Statement
  • Keys
    • SQL Keys
    • SQL Foreign Key
    • Primary Key in SQL
    • Foreign Key in SQL
    • Unique Key in SQL
    • SQL UNIQUE Constraint
    • SQL Primary Key
    • Alternate Key in SQL
    • SQL Super Key
  • Functions
    • SQL Date Function
    • SQL Server Functions
    • SQL String Functions
    • SQL Compare String
    • Timestamp to Date in SQL
    • SQL REGEX
    • SQL Window Functions
    • SQL Syntax
    • SQL CONCAT
    • SQL ALTER TABLE
    • SQL MOD()
    • SQL Timestamp
    • SQL Min and Max
    • SQL TO_DATE()
    • SQL DATEADD()
    • SQL DATEDIFF()
    • SQL HOUR()
    • SQLite? functions
    • ANY in SQL
    • LIKE Query in SQL
    • SQL NOT NULL
    • SQL NOT IN
    • SQL MAX()
    • SQL MIN()
    • SQL SUM()
    • SQL COUNT
    • SQL identity
    • SQL DELETE Trigger
    • SQL Declare Variable
    • SQL Text Search
    • SQL COUNT DISTINCT
    • SQL TEXT
    • SQL Limit Order By
    • BETWEEN in SQL
    • LTRIM() in SQL
    • TOP in SQL
    • SQL Select Top
    • Merge SQL
    • SQL TRUNCATE()
    • SQL UNION
    • SQL ALL
    • SQL INTERSECT
    • SQL Alias
    • SQL Server Substring
    • CUBE in SQL
    • SQL RANK()
    • SQL CTE
    • SQL LAG()
    • SQL MID
    • SQL avg()
    • SQL WEEK
    • SQL DELETE
    • SQL DATEPART()
    • SQL DECODE()
    • SQL DENSE_RANK()
    • SQL NTILE()
    • SQL NULLIF()
    • SQL Stuff
    • SQL Ceiling
    • SQL EXISTS
    • SQL LEAD()
    • SQL COALESCE
    • SQL BLOB
    • SQL ROW_NUMBER
    • SQL Server Replace
    • SQL Ranking Function
    • SQL Server Permission
  • T-SQL
    • T-SQL pivot
    • T-SQL Formatter
    • T-SQL TRY CATCH
    • T-SQL CTE
    • T-SQL CASE
    • T-SQL DATEPART
    • T-SQL Date Format
    • T-SQL ROUND
    • T-SQL Loop
    • T-SQL IIF
    • T-SQL Union
    • T-SQL CREATE TABLE
    • T-SQL INSERT
    • T-SQL Stuff
    • T-SQL ISNULL
    • T-SQL ADD Column
    • T-SQL DATEDIFF
  • Joins
    • Join Query in SQL
    • Types of Joins in SQL
    • Types of Joins in SQL Server
    • SQL Inner Join
    • SQL Join Two Tables
    • SQL Delete Join
    • SQL Left Join
    • LEFT OUTER JOIN in SQL
    • SQL Right Join
    • SQL Cross Join
    • SQL Outer Join
    • SQL Full Join
    • SQL Self Join
    • Natural Join SQL
    • SQL Multiple Join
  • Advanced
    • MDF File in SQL Server
    • SQL Aliases
    • SQL Hosting
    • SQL Auto Increment
    • SQL Injection
    • SQL Wildcards
    • SQL Check
    • SQL Indexes
    • Select Distinct
    • SQL BETWEEN
    • SQLPlus spool
    • SQL Create Table
    • SQL Schema
    • Comparison Operators in SQL
    • SQL_plus
    • SQL Formatter
    • SQL LEFT INNER JOIN
    • SQL Plus Command
    • SQLPlus not found
    • SQL Injection Attack
    • Aggregate Functions in SQL
    • SQL REVOKE
    • SQL Select Distinct Count
    • IF ELSE Statement in SQL
    • SQL CASE Statement
    • SQL While Loop
    • SQL BIGINT
    • SQL Crosstab
    • SQL Wildcard Character
    • SQL INSTR()
    • SQL now
    • SQL synonyms
    • SQLite?export to csv
    • What is Procedure in SQL
    • Stored Procedure in SQL?
    • SQL Server Constraints
    • SQL DELETE ROW
    • Column in SQL
    • Table in SQL
    • SQL Virtual Table
    • SQL Merge Two Tables
    • SQL Table Partitioning
    • SQL Temporary Table
    • SQL Clone Table
    • SQL Rename Table
    • SQL LOCK TABLE
    • SQL Clear Table
    • SQL DESCRIBE TABLE
    • SQL Mapping
    • Cursors in SQL
    • AND in SQL
    • Wildcard in SQL
    • SQL FETCH NEXT
    • SQL Views
    • SQL Delete View
    • Triggers in SQL
    • SQL UPDATE Trigger
    • SQL AFTER UPDATE Trigger
    • SQL Update Statement
    • SQL DROP TRIGGER
    • SQL DROP Table
    • Types of SQL Views
    • SQL Port
    • SQL Clustered Index
    • SQL COMMIT
    • Distinct Keyword in SQL
    • PARTITION BY in SQL
    • SQL Set Operators
    • SQL UNION ALL
    • Metadata in SQL
    • SQL Bulk Insert
    • Array in SQL
    • SQL REGEXP
    • JSON in SQL
    • SQL For loop
    • EXPLAIN in SQL
    • ROLLUP in SQL
    • Escape Character SQL
    • SQL Cluster
    • SQL Backup
    • SQL Pattern Matching
    • SQL Users
    • ISNULL SQL Server
    • SQL pivot
    • SQL Import CSV
    • SQL if then else
    • SQL ignore-case
    • SQL Matches
    • SQL Search String
    • SQL Column Alias
    • SQL extensions
    • SQL Substring Function
    • Charindex SQL
  • SqlAlchemy
    • What is SQLAlchemy
    • SqlAlchemy ORM
    • SQLAlchemy count
    • SQLAlchemy update object
    • SQLAlchemy pip
    • SQLAlchemy Connection
    • SQLAlchemy Transaction
    • SQLAlchemy Metadata
    • SQLAlchemy Raw SQL
    • SQLAlchemy Filter in List
    • SQLAlchemy Alias
    • SQLAlchemy unique
    • SQLAlchemy JSONB
    • SQLAlchemy Async
    • SQLAlchemy Types
    • SQLAlchemy Many to Many
    • SQLAlchemy Example
    • SQLAlchemy Model
    • SQLAlchemy Data Types
    • SQLAlchemy Filter
    • SQLAlchemy SQLite
    • SQLAlchemy DateTime
    • SQLAlchemy create_engine
    • SQLAlchemy Delete
    • SQLAlchemy Migrations
  • NoSQL
    • NoSQL Databases List
    • NoSQL Data Modeling
    • Types of NoSQL Databases
    • NoSQL Injection
    • NoSQL vs SQL Databases
    • NoSQL Use Cases
    • NoSQL Key Value

SQL Interview Questions

By Priya PedamkarPriya Pedamkar

SQL Interview Questions

Introduction to SQL Interview Questions And Answers

So you have finally found your dream job in SQL but are wondering how to crack the SQL Interview and what could be the probable 2022 SQL Interview Questions. Every interview is different and the scope of a job is different too. Keeping this in mind we have designed the most common SQL Interview Questions and Answers for 2023 to help you get success in your interview.

Below is the list of 2023 SQL Interview Questions and Answers, which can be asked during an interview for fresher and experience. These top interview questions are divided into two parts:

Start Your Free Data Science Course

Hadoop, Data Science, Statistics & others

Part 1 – SQL Interview Questions (Basic)

This first part covers basic interview questions and answers

1. What is SQL?

Answer:
SQL stands for a structured query language, and it is used to communicate with the database. This is a standard language used to perform several tasks such as retrieval, updating, insertion, and deletion of data from a database.

2. Write the query to find the employee record with the highest salary.

Answer:
Select * from table_name where salary = (select max(salary) from table_name);
For example
Select * from employee where salary =(select max(salary) from employee);

3. write the query to find the 2nd highest salary in the employee table?

Answer:
These is the basic SQL interview questions asked in a SQL interview. There are multiple ways to solve this question, below three are the easiest solution for it.
1st: Select max (salary) from employee where salary not in (select max(salary) from employee).
Note: This solution is only to find the 2nd highest salary, if the question gets changed, find the 3rd or 4th highest salary then this will not work. You need to execute the below query for finding nth highest salary.
2nd: Select Salary from employee where salary in (select salary from employee where level = &topnth connect by prior Salary > Salary group by level).
Note: If you run the above query it will ask for entering the value of topnth, if you enter 2 it will show the result for 2 and if you enter 3 it will give the result for 3 likewise this query is generic.
3rd: Select salary from employee where salary in (select salary from (select unique salary from employee order by salary desc) group by rownum, salary having rownum = &topnth).
Execute as same as 2nd query execute.

4. write the query to find the 2nd lowest salary in the employee table?

Answer:
There are multiple ways to solve this question, below two are the easiest solution for it.
1st: Select min (salary) from employee where salary not in (select min(salary) from employee).
Note: This solution is only to find the 2nd lowest salary, if the question gets changed, find the 3rd or 4th lowest salary then this will not work. You need to execute the below query for finding nth highest salary.
2nd: Select Salary from employee where salary in (select salary from employee where level = &lownth connect by prior Salary < Salary group by level).
Note: If you run the above query it will ask for entering the value of lownth, if you entering 2 it will show the result for 2 and if you enter 3 it will give the result for 3 likewise this query is generic.

5. what is the difference between NVL and NVL2 functions?

Answer:
Both the function is used to convert a NULL value to an actual value
NVL: Syntax
NVL (EXPR1, EXPR2)
EXPR1: Is the source value or expression that may contain NULL.
EXPR2: Is the target value for converting NULL.
Note: If EXPR1 is character data then EXPR2 may any data type.
For example: select NVL (100,200) from dual
Output: 100
Select NVL(null,200) from dual;
Output: 200

NVL2: Syntax
NVL2(expr1,expr2,expr3)
If expr1 is not null, NVL2 returns expr2. If expr1 is null then, NVL2 returns expr3.
The data type of the return value is always the same as the data type of expr2 unless expr2 is character data.
Example: select nvl2(100,200,300) from dual;
Output: 200
Select nvl2 (null,200,300) from dual;
Output: 300

6. write the query to find the distinct domain from the email column, consider the below employee table for example?

Name Email
Anubhav [email protected]
Basant [email protected]
Sumit [email protected]
Amit [email protected]

So write the query to get the result only @gmail.com, @yahoo.in, @hotmail.com (Since we have two gmail.com and we need to fetch only a distinct domain).

Answer:
Select distinct (substr (Email, Instr (Email,’@’,1,1))) from employee;

Part 2 – SQL Interview Questions (Advanced)

Let us now have a look at the advanced Interview Questions.

7. Write the query to find the duplicate name and its frequency in the table, consider the below Employee table for reference?

Name Age Salary
Anubhav 26 50000
Anurag 29 60000
Basant 27 40000
Rahul 28 45000
Anubhav 27 48000

Answer:
Select Name, count(1) as frequency from Employee
Group by Name having count(1) > 1

8. Write the query to remove the duplicates from a table without using a temporary table?

Answer:
This is the advanced SQL Interview Questions asked in an interview. Delete from Employee where name in (Select name from employee group by age, salary having count(*) > 1));
Or
Delete from employee where rowid not in (select max (rowid) from employee group by name);

9. Write the Query to find odd and even records from the table?

Answer:
For even number
Select * from employee where empno in (select empno from employee group by empno, rownum having mod(rownum,2) = 0);
For odd number:
Select * from employee where empno in (select empno from employee group by empno, rownum having mod(rownum,2) != 0);

Let us move to the next SQL Interview Questions.

10. Write a SQL query to create a new table with data and structure copied from another table, create an empty table with the same structure as some other table?

Answer:
create a new table with data and structure copied from another table
Select * into new table from an existing table;
Create an empty table with the same structure as some other table
Select * into new_table from existing_table where 1=2;
Or
Create table new table like an existing table;

11. Write a SQL query to find the common records between two tables?

Answer:
Select * from table_one
Intersect
Select * from table_two;

12. Write a SQL query to find the records that are present in one table but missing in another table?

Answer:
Select * from table_one
Minus
Select * from table_two;

Recommended Article

This has been a basic guide to the List Of SQL Interview Questions and answers so that the candidate can crackdown on these SQL Interview Questions easily. You may also look at the following articles to learn more –

  1. TSQL Interview Questions
  2. NoSQL Interview Questions And Answers
  3. Cloud Computing Interview Questions
  4. Interview Question for Java Full Stack Developer
Popular Course in this category
MS SQL Training (16 Courses, 11+ Projects)
  16 Online Courses |  11 Hands-on Projects |  70+ Hours |  Verifiable Certificate of Completion
4.5
Price

View Course

Related Courses

JDBC Training (6 Courses, 7+ Projects)4.9
PHP Training (5 Courses, 3 Project)4.8
Windows 10 Training (4 Courses, 4+ Projects)4.7
SQL Training Program (10 Courses, 8+ Projects)4.7
PL SQL Training (4 Courses, 2+ Projects)4.7
Oracle Training (17 Courses, 8+ Projects)4.7
Primary Sidebar
Footer
About Us
  • Blog
  • Who is EDUCBA?
  • Sign Up
  • Live Classes
  • Corporate Training
  • Certificate from Top Institutions
  • Contact Us
  • Verifiable Certificate
  • Reviews
  • Terms and Conditions
  • Privacy Policy
  •  
Apps
  • iPhone & iPad
  • Android
Resources
  • Free Courses
  • Database Management
  • Machine Learning
  • All Tutorials
Certification Courses
  • All Courses
  • Data Science Course - All in One Bundle
  • Machine Learning Course
  • Hadoop Certification Training
  • Cloud Computing Training Course
  • R Programming Course
  • AWS Training Course
  • SAS Training Course

ISO 10004:2018 & ISO 9001:2015 Certified

© 2023 - EDUCBA. ALL RIGHTS RESERVED. THE CERTIFICATION NAMES ARE THE TRADEMARKS OF THEIR RESPECTIVE OWNERS.

EDUCBA
Free Data Science Course

Hadoop, Data Science, Statistics & others

By continuing above step, you agree to our Terms of Use and Privacy Policy.
*Please provide your correct email id. Login details for this Free course will be emailed to you
EDUCBA

*Please provide your correct email id. Login details for this Free course will be emailed to you

Let’s Get Started

By signing up, you agree to our Terms of Use and Privacy Policy.

EDUCBA

*Please provide your correct email id. Login details for this Free course will be emailed to you
EDUCBA

*Please provide your correct email id. Login details for this Free course will be emailed to you
EDUCBA Login

Forgot Password?

By signing up, you agree to our Terms of Use and Privacy Policy.

This website or its third-party tools use cookies, which are necessary to its functioning and required to achieve the purposes illustrated in the cookie policy. By closing this banner, scrolling this page, clicking a link or continuing to browse otherwise, you agree to our Privacy Policy

Loading . . .
Quiz
Question:

Answer:

Quiz Result
Total QuestionsCorrect AnswersWrong AnswersPercentage

Explore 1000+ varieties of Mock tests View more