Null Values in a List item:

A Form  Builder  creates  a pseudochoic in the list to represent the null if  the  base  table  column  for  a  list  item  accepts  NULL  values.

The below given all three list styles display a blank field if a query returns a NULL value.  If the data needs property is set to Yes, upon activation list items show a blank element.

• The poplist shows a blank element for a NULL value.
• The user has to scroll through to display the blank element For Tlists.
• A combo box does not show a blank element. An end user must delete the default value if the default value is not NULL.