DLOOKUP, DSUM, DMAX etc

Is there a video that shows how I can do this or something very similar?

Did you watch any of the video of the links I provided in my first reply?

Thanks Alex.  I have now, this is exactly what I needed. I am going to attempt using the DMAX function to find the most recent payment date however, I will need to a query instead of a table and use multiple criteria which will probably give a little grief with the concatenation, but I will rewatch Richard's video on that as well.

I added a text box to the form to show the last payment date and placed this in the control source:
=DMax("[PostingDate]","[WebCustLedgerEntry]","CustomerNo=" & [CustNo])
It didn't work.  Any ideas?

I'm sorry I forgot I had to have multiple criteria.  Here is what I have now as the control source but this too doesn't seem to work either.

=DMax("PostingDate","WebCustLedgerEntry","CustomerNo=" & [CustNo] And "DocumentType=""Payment""")

Is CustomerNo an actual number in the Field Type?

Hi Alex.  Look at the image.  It's name of field in the WebCustLedgerEntry table.  Also, with what I put into my last message this seems to now find just the latest entry in the table but not the latest payment entry.

The image doesn't give the data type of the field

You need to treat the parameter as a string so wrap it in quotes.

No matter how I try to wrap the criteria in quotes I keep getting an error.

=DMax("PostingDate","WebCustLedgerEntry","CustomerNo=" & [CustNo] And "DocumentType=""Payment""")

Please help with sytax for wrapping the criteria in quotes" by changing my current dmax statement

Double Double Quotes

Thanks for trying Alex.  I guess I'm just not getting it.  Could someone else please just copy my sytax and paste it with the correct syntax?

Double Double Quotes was also covered in:
Access Expert 10
Access Expert 29

Go back and review these classes.

I've watched both a few times and also still just can't seem to get it to work.  Thanks for trying to help.  I guess I will wait until someone can paste the proper sytax.

Try Concatenation that's also a problem you have currently. Maybe you can figure out the double quotes once you fix that. The problem is here [CustNo] And "

Once you've watched that video if you still can't get it I'll give you the answer, but that's a pretty important part of making criteria so make sure you watch it.

I've tried it over a few dozen ways.  This was my last attempt and still no joy.
=DMax("PostingDate","WebCustLedgerEntry","CustomerNo=""" & [CustNo] &""" And "DocumentType=""Payment""")

I've spent over 3hrs on this.

Try =dmax("postingdate",webcustledgerentry","customerno=""" & custno & """ and documenttype="

Is payment a field or a word?

Documenttype=""payment""")

Or if field

Documenttype=""" & payment & """")

Thanks so much. I will try it again tomorrow when i get back to the office. Yes Payment is a word not a field.

Also you started with
=DMax("[PostingDate]","[WebCustLedgerEntry]","CustomerNo=" & [CustNo])

Before trying with a dynamic value try hard coding.

=DMax("[PostingDate]","[WebCustLedgerEntry]","CustomerNo='1'")

Replace 1 with an actual number.

Then when that's working, try adding a second criteria.
Then when that's working try substituting the 1 for a dynamic value.

Thanks Adam. That worked.  I can see my mistake.  It was the concatenation of the first criteria.  I thought I had firm grasp on concatenation until yesterday...  Alex, thank you very much as well. The syntax that you both helped me with and actually worked wasn't covered in any of the videos I could find.  

Just one more question, when using DMAX, DSUM, DMIN, DLOOKUP, etc... will that concatenation syntax hold true for the criteria portion of all these functions?

Yes it is the same syntax for all those functions.

Study that concatenation! :)