Urgent: Using null in the selection formula!!!

[mazhar]

I have a query in Oracle which I am porting to Access. My reports will be using Access as database. In the where condition of the query, I have to check for the following:
customer_id is null

How do I put a check for the above? When I try like {customer.customer_id} is null in selection formula, it is giving 'error in formula' message.

Thanks

 

[KirkH]

You must use the IsNull() function.

 

[Guest_imported]

the format is
isnull({cusomer.customer_id})

 

[mazhar]

Hi Helen,


Sorry. You got my question wrong. I don't want to check whether customer id is null or not. I want to make a condition which says that customer_id must be null. Got it?
(Here customer_id is a nullable field and for some combinations, customer_id should be null)

where clause looks something like

customers_broker = user input AND customer_id is null

If you can't get my question right, give me your personal mail id; I will send you original query. Sorry for the trouble and Thanks once again.

 

[MalcolmW]

To make a condition which says the customer id must be null, you will have to check whether the customer id is null. IsNull(customer_id) is True when customer id is null, otherwise false.
An example is
customers_broker = user input AND IsNull(customer_id)
Try it - you might like it.