IN NULL vs IS NULL – 1Z0-061 Oracle SQL

This is one more common mistake the one can make when it comes to NULL engaged with comparison

Consider these two statements, they will produce different results:

select * from emp where commission_pct in (0.1, NULL) ; 
select * from emp where commission_pct = 0.1 or commission_pct IS NULL ;

In the first statement, NULL won’t be caught, because it is equivalent to

select * from emp where commission_pct = 0.1 or commission_pct = NULL ;

While the second query will work just fine because NULL is being processed correctly