Null's vs Empty string

I'm just starting to use Oracle, so this question is just because of lack of knowledge and experience.

We are converting/testing an application, written in CA/OpenRoad, to run against Oracle. Originally it's using OpenIngres.

The OpenIngres database has many varchar columns defined with the 'NOT NULL' option. If the user leaves entry fields empty a SQL Insert (or Update) statement will be generated:  INSERT INTO table (key, char_column)

        VALUES (1, ''); This works fine with OpenIngres. However, Oracle seems to convert the empty string to a NULL value, resulting in an error on the Insert/Update.

I always assumed null's have been introduced to make the distinction between 'unknown' and 'empty' (or zero), so I'm wondering if this is possible within Oracle ?
Can I influence this '' to null conversion with some setting ?

Thanks in advance. Received on Sun Oct 27 1996 - 00:00:00 CEST