In Oracle SQL / PLSQL IS NULL is used to check whether the value of a literal is NULL or not.
Syntax to use IS NULL in IF statement is:
IF literal_name IS NULL THEN
Here if the literal_name has NULL value then the IF condition will evaluate to TRUE, then the “THEN” section of the code will get executed.
Using IS NULL is Oracle SQL / PLSQL SELECT statement:
Suppose we have a table named ‘employee’ as shown below:
Suppose we want to see the records having commission as NULL, then we can achieve the same as:
SELECT * FROM employee WHERE commission IS NULL;
We will get the following results:
Here we can see that we have successfully retrieved records having NULL commission using IS NULL in Oracle SQL PLSQL SELECT statement.