EDUCBA

EDUCBA

MENUMENU
  • Free Tutorials
  • Free Courses
  • Certification Courses
  • 360+ Courses All in One Bundle
  • Login
Home Data Science Data Science Tutorials MySQL Tutorial MySQL IFNULL()
Secondary Sidebar
MySQL Tutorial
  • Functions
    • MySQL Function
    • MySQL Aggregate Function
    • MySQL String functions
    • MySQL Date Functions
    • MySQL Window Functions
    • MySQL Math Functions
    • MySQL Boolean
    • Cursor in MySQL
    • Condition in MySQL
    • MySQL BETWEEN
    • Insert in MySQL
    • MySQL IFNULL()
    • MySQL TIMESTAMPDIFF()
    • MySQL COALESCE()
    • MySQL count()
    • MIN() in MySQL
    • MySQL Numeric
    • MySQL field()
    • MySQL FIND_IN_SET()
    • MySQL avg()
    • MySQL MAX() Function
    • MySQL BIN()
    • MySQL Concat
    • MySQL DECODE()
    • MySQL REGEXP_REPLACE()
    • MySQL Asynchronous
    • MySQL innodb_buffer_pool_size
    • MySQL key_buffer_size
    • MySQL TRUNCATE()
    • MySQL ROW_NUMBER()
    • NOT in MySQL
    • MySQL IN Operator
    • LIKE in MySQL
    • ANY in MySQL
    • MySQL NOT IN
    • MySQL CHECK Constraint
    • MySQL DISTINCT
    • MySQL ALL
    • MySQL Union
    • MySQL UNION ALL
    • MySQL EXISTS
    • MySQL ON DELETE CASCADE
    • MySQL REGEXP
    • MySQL Index
    • MySQL Add Index
    • MySQL REINDEX
    • MySQL UNIQUE INDEX
    • MySQL Clustered Index
    • MySQL? InnoDB Cluster
    • Table in MySQL
    • ALTER TABLE MySQL
    • MySQL Temporary Table
    • MySQL Clone Table
    • MySQL Repair Table
    • MySQL Lock Table
    • MySQL Optimize Table
    • TRUNCATE TABLE MySQL
    • MySQL?Table?Size
    • MySQL Table Dump
    • MySQL Update Set
    • MySQL ALTER TABLE Add Column
    • MySQL RANK()
    • MySQL CTE
    • MySQL LAG()
    • MySQL GROUP_CONCAT()
    • MySQL EXTRACT()
    • MySQL REPLACE
    • MySQL AUTO_INCREMENT
    • MySQL SYSDATE()
    • MySQL NULLIF()
    • MySQL Substring
    • MySQL SUBSTRING_INDEX()
    • MySQL LOWERCASE
    • MySQL Row
    • MySQL NOW
    • MySQL CEIL
    • MySQL Alias
    • MySQL Trigger
    • MySQL SHOW Triggers
    • MySQL UPDATE Trigger
    • MySQL DELETE Trigger
    • MySQL AFTER UPDATE Trigger
    • MySQL Stored Procedure
    • ROLLUP in MySQL
    • MySQL? INSTR()
    • MySQL Subquery
    • MySQL Timestamp
    • MySQL? Hour()
    • MySQL MOD()
    • MySQL DATE_FORMAT()
    • ALTER Column in MySQL
    • MySQL Rename Column
    • MySQL Interval
    • MySQL CURDATE
    • MySQL BIT
    • MySQL Binlog
    • MySQL Average
    • MySQL TEXT
    • MySQL SHOW
    • MySQL Offset
    • MySQL Timezone
    • mysql_real_escape_string
    • MySQL Datetime
    • MySQL DATE_SUB()
    • MySQL FULLTEXT
    • MySQL DATE_ADD()
    • MySQL sum()
    • MySQL Merge
    • MySQL BigInt
    • MySQL ROUND
    • MySQL VARCHAR
    • MySQL Decimal
    • MySQL Limit
    • MySQL today()
    • MySQL WEEKDAY
    • MySQL Split
    • MySQL Create Function
    • MySQL BLOB
    • MySQL encode()
    • MySQL Primary Key
    • MySQL Foreign Key
    • Unique Key in MySQL
    • MySQL Drop Foreign Key
    • MySQL DROP TRIGGER
    • MYSQL Database
    • Delete Database MySQL
    • MySQL Root
    • MySQL Root Password
    • MySQL Client
    • MySQL Users
    • MySQL?User Permissions
    • MySQL add user
    • MySQL List User
    • MySQL Show Users
    • MySQL User Password
    • MySQL?Cardinality
    • MySQL Workbench
    • MySQL Backup
    • MySQL REVOKE
    • MySQL Dump
    • MySQL Cluster
    • MySQL Full Text Search
    • MySQL Admin Tool
    • MySQL Export Database
    • MySQL Export to CSV
  • Basic
    • MySQL floor
    • MySQL DESCRIBE table
    • MySQL encryption
    • Introduction to MySQL
    • Is SQL Server a Database?
    • What is MySQL
    • Is MySQL Programming Language
    • MySQL Server
    • MySQL AB
    • MySQL Community Server
    • How To Install MySQL
    • MySQL Versions
    • MySQL OpenSource
    • MySQL GUI Tools
    • MySQL Grant
    • MySQL Error 1064
    • MySQL Drop Database
    • MySQL not equal
    • MySQL SELECT INTO Variable
    • MySQL Commands
    • MySQL Operators
    • What is MySQL Schema
    • Wildcards in MySQL
    • MySQL Constraints
    • MySQL Administration
    • MySQL Data Type
    • MYSQL COMMIT
    • MySQL FORMAT
    • Timestamp to Date in MySQL
    • MySQL DATEDIFF
    • MySQL?Incremental Backup
    • MySQL JSON Data Type
    • MySQL ENUM
    • MySQL Default Port
    • Cheat Sheet MySQL
  • Queries
    • MySQL Queries
    • MySQL Query Commands
    • SELECT in MySQL
    • MySQL INSERT IGNORE
    • MySQL having
    • ORDER BY in MySQL
    • MySQL Cheat Sheet
    • MySQL ORDER BY Random
    • MySQL ORDER BY DESC
    • MySQL GROUP BY
    • MySQL GROUP BY Count
    • MySQL GROUP BY month
    • MySQL WHERE Clause
    • MySQL WITH
    • MySQL FETCH
    • MySQL DDL
    • MySQL DML
    • MySQL WHERE IN Array
    • MySQL Fetch Array
    • MySQL ISNULL
    • MySQL Index Types
    • Mysql? Export Schema
    • Amazon RDS for MySQL
    • MySQL greatest
  • Database
    • What is Data Modeling
    • What is Data Processing
    • DBMS Architecture
    • DBMS Keys
    • Careers in Database Administration
    • What is MySQL Database
    • MySQL Relational Database
    • How to Connect Database to MySQL
    • MySQL Database Repair
    • RDBMS Interview Questions
    • DBMS Interview Questions
  • Joins
    • Joins in MySQL
    • MySQL Outer Join
    • Left Outer Join in MySQL
    • MySQL Self Join
    • Natural Join in MySQL
    • MySQL DELETE JOIN
    • MySQL Update Join
    • MySQL Cross Join
  • Advanced
    • MySQL Formatter
    • MySQL TINYINT
    • MySQL Grant All Privileges
    • MySQL DROP TABLE
    • MySQL rename database
    • MySQL Flush Privileges
    • MySQL super Privilege
    • MySQL Character Set
    • MySQL Log File
    • MySQL Flush Log
    • Grant Privileges MySQL
    • MySQL WHILE LOOP
    • IF Statement in MySQL
    • MySQL CASE Statement
    • MySQL IF Function
    • MySQL IF EXISTS
    • MySQL UUID
    • Views in MySQL
    • MySQL Replication
    • MySQL Partition
    • Toad for MySQL
    • Navicat for MySQL
    • MySQL AES_Encrypt
    • MySQL Performance Tuning
    • MySQL Transaction
    • MySQL? sort_buffer_size
    • MySQL? Sync
    • MySQL? Query Cache
    • MySQL Collation
    • MySQL ODBC Driver
    • MySQL Partitioning
    • MySQL InnoDB
    • MySQL Float vs Decimal
    • MySQL Union vs Union All
  • Interview Questions
    • MySQL Interview Questions

MySQL IFNULL()

MySQL IFNULL()

Introduction to MySQL IFNULL() function

MySQL IFNULL() function is a control flow function which consists of two arguments expression_1 and alternate_expression. Here expression_1 is returned if the value is NOT NULL else it returns the value of the alternate_expression. If you want to replace a NULL with the alternate expression you desire, then this can be done using IFNULL () function.

The return value of the IFNULL () function can be either string or a numeric value. It basically depends on the context. It’s good practice to avoid IFNULL() function in the WHERE clause as it will degrade the performance instead you can use ISNULL() or IS NOT NULL function.

Start Your Free Data Science Course

Hadoop, Data Science, Statistics & others

In this session let us learn about the IFNULL function and examples of how it is used in real-time scenarios.

Syntax:

Now let us see the syntax of the IFNULL () function: –

ifnull(expression_1, alternate_expression);

In the above syntax if the expression_1 is NULL then alternate_expression value will be returned. If the expression_1 is NOT NULL, then it returns the expression_1 value.

How does IFNULL() function work?

Now let us see how the IFNULL () works:

SELECT IFNULL('HI','HIII')AS Expression; / * - - - IFNULL FUNCTION - - - * /

Here if we check the above statement we can see that the ‘expression_1’ is NOT NULL. So, the output will be the ‘expression_1’. Screenshot is for the same:

Output:

MySQL IFNULL() 1

SELECT IFNULL(NULL,'HIII')AS Expression; / * - - - IFNULL FUNCTION - - - * /

Here if we check the above statement we can see that the ‘expression_1’ is NULL. So, the output will be the ‘alternate_expression’.

Output:

MySQL IFNULL() 2

SELECT IFNULL('','HIII')AS Expression; / * - - - IFNULL FUNCTION - - - * /

Here if we check the above statement we can see that the ‘expression_1’ is NOT NULL. As the empty string is also considered as value. So, the output will be the ‘alternate_expression’. Screenshot is for the same: –

Output:

MySQL IFNULL() 3

Examples of MySQL IFNULL()

The IFNULL() can be applied in the table level as well:

Now let us create a table and apply the IFNULL () function on it:

CREATE TABLE IFNULL_TEST / * - - - Creating IFNULL_TEST table - - - * /
(
Person_FirstName Varchar(20)
,Person_LastName Varchar(20)
,Person_location Varchar(20)
,Person_phoneno Varchar(20)
,Person_Landline Varchar(20)
);

Now let us insert data into the table: -/ * – – – Insert data into the table – – – * /

INSERT INTO IFNULL_TEST VALUES ('Bob','Miley','Norway',NULL,'(567)0772345');
INSERT INTO IFNULL_TEST VALUES ('Mark','Zucker','England','451667287','(567)0772345');
INSERT INTO IFNULL_TEST VALUES ('Fred','Bostan','Holloland',NULL,'(567)0772345');
INSERT INTO IFNULL_TEST VALUES ('Ben','Haminnton','Poland','716672870','(567)0772345');
INSERT INTO IFNULL_TEST VALUES ('William','Haminnton','Paris','231667287',NULL);
INSERT INTO IFNULL_TEST VALUES ('Sam','Miley','Norway',NULL,'(567)0772345');
INSERT INTO IFNULL_TEST VALUES ('Julie','Murray','Norway','29357683','(567)0772345');
INSERT INTO IFNULL_TEST VALUES ('Bobby','stuart','France',NULL,'(567)0772345');

Let us perform select query in the above table. We get below output:

MySQL IFNULL() 4

Now let us perform the IFNULL () function operates on the “Person_Phoneno” column and “Person_Landline” column. We will try to get value in such that if the “Person_Phoneno” IS NULL then get the “Person_Landline” Value into the column. Below is the syntax for the same:

SELECT *,IFNULL(Person_Phoneno,Person_landline)As "Contact details" FROM IFNULL_TEST;

/ * – – – IFNULL FUNCTION – – – * /

We could see the output as follow:

MySQL IFNULL() 5

If we observe the above output we could see that the “Person_landline” value has been displayed whenever we have NULL value in the “Person_phoneno”.

If both the values are NULL we get output as NULL value itself. Below is the example for the same:

SELECT IFNULL(NULL, NULL)AS Expression; / * - - - IFNULL FUNCTION - - - * /

Here if we check the above statement we can see that the ‘expression_1’ is NULL and the alternate_function is also NULL as well. So, the output will be NULL.

Output:

MySQL IFNULL() 6

Example #2

Now let us consider another example for IFNULL () function.

SELECT IFNULL('EXPRESSION_1','HIII')AS Expression; / * - - - IFNULL FUNCTION - -* /

Here if we check the above statement we can see that the ‘expression_1’ is NOT NULL. So, the output will be the ‘expression_1’. Screenshot is for the same:

Output:

example 2

SELECT IFNULL(NULL,'Alternate expression')AS Expression; / * - - - IFNULL FUNCTION - -* /

Here if we check the above statement we can see that the ‘expression_1’ is NOT NULL. So, the output will be the ‘Alternate expression’.

Output:

example 2-1

Recommended Articles

This is a guide to MySQL IFNULL(). Here we discuss the Introduction, How does IFNULL() function works? and examples with code implementation respectively. You may also have a look at the following articles to learn more –

  1. MySQL having
  2. MySQL BLOB
  3. MySQL encode()
  4. MySQL today()
Popular Course in this category
MySQL Training Program (12 Courses, 10 Projects)
  12 Online Courses |  10 Hands-on Projects |  92+ Hours |  Verifiable Certificate of Completion
4.5
Price

View Course

Related Courses

MS SQL Training (16 Courses, 11+ Projects)4.9
Oracle Training (17 Courses, 8+ Projects)4.8
PL SQL Training (4 Courses, 2+ 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