Oracle: Finding Columns with only null values

Question

I have a table with a lot of columns and a type column.

Some columns seem to be always empty for a specific type.

I want to create a view for each type and o

Answer 1

To find rows that have a null-value, use the "is null" condition.

select * from table_A where table_col1 is null;

To do the reverse, and find all the rows with a non-null value, use the "is not null" condition:

select * from table_A where table_col1 is not null;

Nulls in range comparisons:

select * from table_A where table_col1 < 15 or table_col1 is null;