Can you have if-then-else logic in SQL? [duplicate]

Answer 1

Instead of using EXISTS and COUNT just use @@ROWCOUNT:

select product, price from table1 where project = 1

IF @@ROWCOUNT = 0
BEGIN
    select product, price from table1 where customer = 2

    IF @@ROWCOUNT = 0
    select product, price from table1 where company = 3
END