Comment by sixdimensional

A few thoughts.

0 <> NULL <> ""

They are all values that matter because they can exist.

Blank can have business meaning. Also, I suspect that there is a reason blank is separate from NULL in the ASCII table. They are different signals, and changing one to the other is fundamentally changing the meaning of the signal.

Blank often has business meaning on forms, like "leave this field blank to indicate the user has acknowledged the field but chose to enter a blank value" vs the "user never saw this field and no value was entered, or the system did not store a value for the user's input".

The old saying "NULL is not nothing"?