[oracle] How to create a blank/empty column with SELECT query in oracle?

I want to generate an output with blank/empty column with a "Select" query in oracle. I'm able to achieve this with below sql query:

SELECT CustomerName AS Customer, "" AS Contact 
FROM Customers;

So when I run above sql query it returns a table with two columns "Customer" column with content in it and "Contact" column with no content or blank column. I want to achieve same with oracle query. Any help will be highly appreciated.

I guess you will get ORA-01741: illegal zero-length identifier if you use the following

SELECT "" AS Contact  FROM Customers;

And if you use the following 2 statements, you will be getting the same null value populated in the column.

SELECT '' AS Contact FROM Customers; OR SELECT null AS Contact FROM Customers;

In DB2, using single quotes instead of your double quotes will work. So that could translate the same in Oracle..

SELECT CustomerName AS Customer, '' AS Contact 
FROM Customers;

I think you should use null

SELECT CustomerName AS Customer, null AS Contact 
FROM Customers;

And Remember that Oracle

treats a character value with a length of zero as null.