Create recommendation list

[Darren_Murphy]

I thought we solved that issue in your earlier question related to this App?

Add row only if it does not exist

In one table I have a list of book selections by readers. Each row represents a book and a user. When multiple user select the same book, there are multiple rows added. Works fine. I have created a roll-up table that counts how many times each book is in the books table. I cannot figure out how to add the book to the roll-up table at the same time it is added to the books table without creating redundant rows in the roll-up table. The logic would be something like, “if book already exists …