Save Space by Allowing NULL

To save storage space for empty text, unitext, or image columns, define them to permit null values and insert nulls until you use the column. Inserting a null value does not initialize a text, unitext, or image column and, therefore, does not create a text pointer or allocate storage.

For example, the following statement inserts values into the title_id and pub_id columns of the testtext table created above, but does not initialize the blurb text column:

insert texttest
(title_id, pub_id) values ("BU7832", "1389")