Sqliz
sqliz.com › posts › how-isnull-works-in-mariadb
How the ISNULL() function works in Mariadb?
March 6, 2024 - The ISNULL() function returns 1 if the expression is NULL, otherwise, it returns 0.
Xiaolincoding
xiaolincoding.com › interview › mysql.html
MySQL面试题 | 小林coding | Java面试学习
February 27, 2026 - 这篇文章把 MySQL 面试中从基础到进阶的高频考点都整理进来了，包括 SQL 基础、存储引擎、索引原理、事务、锁机制、日志系统，到最后的主从复制和分库分表，基本上是一个比较完整的 MySQL 知识体系。内容偏向原理，不只是告诉你"怎么用"，更多是讲清楚"为什么"。
Videos
Curso Prático de BD MySQL - Where ( is null e is not null ...
05:08
MySQL IS NULL and IS NOT NULL Operators | MySQL Tutorial for ...
07:28
IS NULL vs IS NOT NULL - Curso de SQL - Aula 23 - YouTube
IS NULL in MySQL #mysql #mariadb #sql #databaseconcepts ...
13:27
IfNULL/IsNULL/Coalesce Functions in SQL - YouTube
09:34
MySql 11 | IFNULL() & ISNULL() Functions in MySql - YouTube
DataCamp
datacamp.com › doc › mysql › mysql-is-null
MySQL IS NULL Keyword: Usage & Examples
The IS NULL keyword in MySQL is used to check whether a column contains a NULL value.
MySQLCode
mysqlcode.com › home › mysql isnull() and ifnull() functions
MySQL ISNULL() and IFNULL() Functions - MySQLCode
June 24, 2022 - The MySQL ISNULL() function is used to check for any NULL values in the expression passed to it as a parameter. If the expression has/results to NULL, it displays 1.
W3Schools
w3schools.com › sql › func_mysql_isnull.asp
MySQL ISNULL() Function
SELECT ISNULL("Hello world!"); Try it Yourself » · ❮ Previous ❮ MySQL Functions Next ❯ · ★ +1 · Sign in to track progress · REMOVE ADS · PLUS · SPACES · GET CERTIFIED · FOR TEACHERS · BOOTCAMPS · CONTACT US · × · If you want to use W3Schools services as an educational institution, team or enterprise, send us an e-mail: sales@w3schools.com ·
SQL Academy
sql-academy.org › functions mysql › isnull
ISNULL — MySQL Function Reference
A comprehensive guide to SQL functions with examples for MySQL and PostgreSQL - Find out how the ISNULL function works in SQL MySQL. Returns 1 or 0 depending on whether the expression is NULL
Sqliz
sqliz.com › mariadb-ref › isnull
MariaDB ISNULL() Function
In MariaDB, ISNULL() is a built-in function that returns 1 if the gaven parameter is NULL, otherwise returns 0.
Database Guide
database.guide › sql-isnull-explained
SQL ISNULL() Explained
Some RDBMSs provide an ISNULL() function that can be used when dealing with potentially null values. MySQL, MariaDB, and Oracle Database each have an ISNULL() function that returns 1 if its argument is null, and 0 if it’s not.
W3Schools
w3schools.com › sql › sql_null_values.asp
SQL NULL Values - IS NULL and IS NOT NULL
String Functions: ASCII CHAR CHARINDEX CONCAT Concat with + CONCAT_WS DATALENGTH DIFFERENCE FORMAT LEFT LEN LOWER LTRIM NCHAR PATINDEX QUOTENAME REPLACE REPLICATE REVERSE RIGHT RTRIM SOUNDEX SPACE STR STUFF SUBSTRING TRANSLATE TRIM UNICODE UPPER Numeric Functions: ABS ACOS ASIN ATAN ATN2 AVG CEILING COUNT COS COT DEGREES EXP FLOOR LOG LOG10 MAX MIN PI POWER RADIANS RAND ROUND SIGN SIN SQRT SQUARE SUM TAN Date Functions: CURRENT_TIMESTAMP DATEADD DATEDIFF DATEFROMPARTS DATENAME DATEPART DAY GETDATE GETUTCDATE ISDATE MONTH SYSDATETIME YEAR Advanced Functions CAST COALESCE CONVERT CURRENT_USER IIF ISNULL ISNUMERIC NULLIF SESSION_USER SESSIONPROPERTY SYSTEM_USER USER_NAME MS Access Functions
InterviewBit
interviewbit.com › sql-interview-questions
SQL Interview Questions CHEAT SHEET (2026) - InterviewBit
The key difference here, compared to DBMS, is that RDBMS stores data in the form of a collection of tables, and relations can be defined between the common fields of these tables. Most modern database management systems like MySQL, Microsoft SQL Server, Oracle, IBM DB2, and Amazon Redshift are based on RDBMS.
Published 1 month ago
CerebroSQL
cerebrosql.com › en › sql-tutorial-for-mysql › 72
MySQL tutorial: ISNULL [EN]
Syntax: ISNULL(expr) If expr is NULL, ISNULL() returns 1, otherwise it returns 0. mysql> SELECT ISNULL(1+1); -> 0 mysql> SELECT ISNULL(1/0); -> 1
TechOnTheNet
techonthenet.com › mysql › functions › isnull.php
MySQL: ISNULL Function
If expression is a NULL value, the ISNULL function will return 1.
DataCamp
datacamp.com › doc › mysql › mysql-ifnull
MySQL IFNULL Keyword: Usage & Examples
The `IFNULL` keyword in MySQL is a function used to handle NULL values by providing an alternative value.
w3resource
w3resource.com › mysql › comparision-functions-and-operators › is-null().php
MySQL ISNULL() function - w3resource
March 3, 2026 - MySQL ISNULL() function returns 1 when the expression is NULL otherwise it returns 0.
Top answer 1 of 2
6
They server two completely different functions.
ISNULL(value) is a boolean operator that returns 1 or 0 depending on whether or not the value passed in is null. It can be used in if and case statements to determine logic flow. Example:
SELECT OrderID,
CASE
WHEN ISNULL(AmountDue) THEN "Paid in full"
WHEN DATE(DueDate) < date(NOW()) THEN "Order is past due"
ELSE CONCAT("Order is due on ", CONVERT(VARCHAR, DueDate, 121))
END
FROM OrderDetails;
IFNULL(value1, value2) is used to handle a situation where you want one value, unless it is null, in which case you want a second value. Example:
select IFNULL(MiddleName, "No Middle Name") from customers
2 of 2
2
In MySQL, ISNULL simply checks if a value is null or not. IFNULL acts like COALESCE and will return the 2nd value if the first value is null.
Are you perhaps mistaking ISNULL in SQL Server as the one in MySQL? In SQL Server ISNULL is the same as IFNULL in MySQL.
Naukri
naukri.com › code360 › library › mysql-isnull
MySQL ISNULL - Naukri Code 360
May 2, 2024 - Almost there... just a few more seconds
TechOnTheNet
techonthenet.com › mariadb › functions › isnull.php
MariaDB: ISNULL Function
SELECT ISNULL('TechOnTheNet.com'); Result: 0 SELECT ISNULL('T'); Result: 0 SELECT ISNULL(''); Result: 0 SELECT ISNULL(52); Result: 0 SELECT ISNULL(NULL); Result: 1 · Share on: SQL · Oracle / PLSQL · SQL Server · MySQL · MariaDB · PostgreSQL · SQLite · Excel ·
ThoughtSpot
thoughtspot.com › sql-tutorial
ThoughtSpot SQL Tutorial | ThoughtSpot
March 12, 2026 - Learn to answer questions with data using SQL, no prior coding required, guiding you through foundational to advanced SQL skills.
W3Schools
w3schools.com › mysql › mysql_notnull.asp
MySQL NOT NULL Constraint
String Functions ASCII CHAR_LENGTH ... CASE CAST COALESCE CONNECTION_ID CONV CONVERT CURRENT_USER DATABASE IF IFNULL ISNULL LAST_INSERT_ID NULLIF SESSION_USER SYSTEM_USER USER VERSION · MySQL Examples MySQL Editor MySQL Quiz MySQL Exercises MySQL Syllabus MySQL Study ...
W3Schools
w3schools.com › sql › func_sqlserver_isnull.asp
SQL Server ISNULL() Function
ADD ADD CONSTRAINT ALL ALTER ALTER COLUMN ALTER TABLE ALTER VIEW AND ANY AS ASC BACKUP DATABASE BETWEEN CASE CHECK COLUMN CONSTRAINT CREATE CREATE DATABASE CREATE INDEX CREATE OR REPLACE VIEW CREATE TABLE CREATE PROCEDURE CREATE UNIQUE INDEX CREATE VIEW DATABASE DEFAULT DELETE DESC DISTINCT DROP DROP COLUMN DROP CONSTRAINT DROP DATABASE DROP DEFAULT DROP INDEX DROP TABLE DROP VIEW EXEC EXISTS FOREIGN KEY FROM FULL OUTER JOIN GROUP BY HAVING IN INDEX INNER JOIN INSERT INTO INSERT INTO SELECT IS NULL IS NOT NULL JOIN LEFT JOIN LIKE LIMIT NOT NOT NULL OR ORDER BY OUTER JOIN PRIMARY KEY PROCEDURE RIGHT JOIN ROWNUM SELECT SELECT DISTINCT SELECT INTO SELECT TOP SET TABLE TOP TRUNCATE TABLE UNION UNION ALL UNIQUE UPDATE VALUES VIEW WHERE MySQL Functions