I am trying to produce a report showing certain transactions allocated to a particular incident. In one particular case I need to check if a particular incident has one of two specific transaction types, if it does then it should use one of them, but never both. Is there a clean way of doing this. The only way I can think of is using subqueries/table aliases and coalesce to get the result. I would still need the other transaction types included if they had been entered.