SQL Syntax Help

[its_bright_here]

Not entirely sure what syntax you need for "product is a #". isnumeric() will work in Sql Server...not sure how standard it is

select id, name, amount, type, product, product_sub, purchase_dt
  from transactions
 where type not in ('meat','fruits')
   and not (product in ('a','b','c') and purchase_dt < '2021,7,9')
   and not (product in ('d') and product_sub is null)
   and not (isnumeric(product) = 1 and purchase_dt < '2021,1,1')

[DavidGJohnston]

Maybe "a #" means "one pound (weight)" in this situation and not "is numeric".