Presumably, your form has an associated table. In the Manage Database dialog,on your Relationships Graph, create a relationship between the part number field in the form table and the part number field in the table that has all the 56,000 line items.
Then, choose the supplier field and click "Options". On the Auto-Enter tab, choose Lookup. Select the part number table and choose the supplier field. Now whenever, you enter the part number in the form table, it will automatically copy the supplier into the form.
As an aside, this is one way to do it. You would use this method if you want to keep the supplier information static on the form - in other words, if the supplier information ever changes, you don't want the information on the form to change. This might be appropriate for invoicing, for example. However, if you want the supplier information to update whenever it changes in the imported data, then you wouldn't have a supplier name field in the form table at all. You'd just use the one in the part number table and put that on the form instead. (Which, BTW, would be a more normal arrangement in a relational database.)
Short version: You can either do it as a lookup (static, non-normalized), or as a related field (dynamic, normalized). It depends on your business flow.
These were fantastic instructions and worked like a charm the first time!!! Thank you!! Thank you!!
Mike, I have a similar situation except that the field that needs to auto populate on my paper form is in a portal (usually on row 2 or 4) in one of my layouts. This may not be enough information but, any ideas?
Where the field is doesn't really matter. You still join the two tables together. You do have to pay attention to which table, since a portal usually references fields in a different table than the one on which the layout is based.
Now, if something else is going on and the lookup isn't working, then yes, we'd need more information.
Understood. I will visit this tomorrow and see what happens but I don't think my case is that simple.