Filtering out blank spaces

Question

I want to query a table and get all rows where the column i_vhcl_recal is not empty. I ran the following below and kept getting rows that appeared to be empty. Upon inspection, that the fields weren't null but instead they were a string of blank spaces.

How to I query rows where i_vhcl_recal has an actual value and not blank spaces or nulls?

SELECT * 
FROM table 
WHERE i_vhcl_recal IS NOT NULL

Answer 1

Try this:

SELECT * 
FROM table 
WHERE (i_vhcl_recal <> '') IS NOT TRUE;

Answer 2

You could do this with a regex:

select * from table where i_vhcl_recal is not null and i_vhcl_recal !~ '^\s*$';

The interesting thing about '\\s' is that it matches on a variety of space characters such as: carriage return, line feed, horizontal tab, vertical tab, form feed.