Using “Is Null” as a criteria based on a form

问题

I'm trying to get my query to only return null records if a radio box on a form is ticked. If I manually include the criteria Is Null in the query it works just fine, and elsewhere things like

IIf([Forms]![Reports]![Status - Active]=True,"Active")

work just fine.

However,

IIf([Forms]![Reports]![Status - Null]=True,"Is Null")

just ignores it (I assume because it's actually looking for the text "Is Null" rather than null records) and

IIf([Forms]![Reports]![Status - Null]=True,Is Null)

fails because it's too complex. Is there any way of achieving what I'm trying to achieve?

Thanks.

回答1:

You could work around in a couple of ways, for example.

SELECT t.atext
FROM Table1 t
WHERE IsNull([atext])=[Forms]![Reports]![Status - Null]

BTW, Immediate If (IIf) takes three arguments.

来源：https://stackoverflow.com/questions/13413987/using-is-null-as-a-criteria-based-on-a-form