Is Null Criteria in a DSum Expression

[djgolds]

I want to be able to sum all of my outstanding invoices within a form I've created for the specific customer record that is active. My expression is:
=DSum("[Amount]","[Invoices]","[CompanyID]=[txtCompanyID] AND [InvoiceDate]='is null'&quot

But this just produces an error message. How do I get it to sum the amounts of invoices where the invoice date is blank because I haven't received payment yet? Thanks in advance for your help!!!

 

[rafe]

take out the "=" so it's...

=DSum("[Amount]","[Invoices]","[CompanyID]='" & [txtCompanyID] & "' AND [InvoiceDate] Is Null&quot

assuming [txtCompanyID] is, in fact, a text field & not a literal

if it's a form control then replace [txtCompanyID] with Me.txtCompanyID

 

[Rohdem]

I beleive that you need to say:
Is Null([Invoice Date])
Mike Rohde
rohdem@marshallengines.com

 

[rafe]

i did test before i posted so i know it works in A2K... tho Mike's solution looks elegant

 

[Rohdem]

I stand corrected
Mike Rohde
rohdem@marshallengines.com