if I understand correctly, you are trying to assign 3 fields - Product Name, Brand and Category - when the Product row with the Barcode exists. correct?
You would actually want to take advantage of REF columns here and using “dot” notation to retrieve values.
The short of it would be, add a “Product” as a Ref column. Assign it with an expression like:
Then in the table you are currently setting up you can use “dot” notation like this:
Product Name - assign the Formula column as - [Product].[Product Name]
Brand - assign the Formula column as - [Product].[Brand]
Category - assign the Formula column as - [Product].[Category]
If the Product column is blank - i.e. row does not exist, then the fields remain blank. If Product is populated, then the fields will be assigned whatever values are in the Products table. If the Product is changed, the fields will update accordingly.
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