Thank you for sharing your questions in PI Square!
I believe in order to do that you should firstly link the SQL table to your AF Database. Then a Table Lookup Data Reference (TLDR) attribute will perform the query to that table and show the result. Finally you will be able to add the value of this TLDR to the notification message.
Would this work for you?
I was thinking about the same solution you have mentioned.
This is not a good solution for me because table must be dynamically expanded or reduced (number of rows).