APEX

Apex 4.2

I have an apex report with several columns

select user_id, name, address, phone, date_finished
from USERS

The 'user_id' field is the primary key and in my apex form has been changed to a column link. It'll take you to a page where you can edit the information. In this report, some information in each row is filled out and some isn't. For example, date_finished will be null or not null. I want a conditional to show/hide the edit links depending on if date_finished is null or not null. In this case, if date_finished is NULL, then the column link to that row should be shown

I tried using:
condition type: Value of Item/Column in expression 1 is NULL
Expression: date_finished

However this, this controls the entire column and either shows all the links to each row or hides all the links to each row (Depending if I change the condition type to NOT NULL instead of NULL)

How can I just hide/show the edit link for the row??