SQL - 需要查找重复记录但是EXCLUDE反转事务

I have a table of transactions which will occasionally have duplicate entries. If/When an admin finds these duplicate entries, they will reverse the transactions, therefore creating a negative value (but the original duplicate still remains due to regulatory requirements). I'd like to create a SQL query (and use Crystal Reports) to make a report for the admins to easily find duplicate transactions. Due to the mass quantity of transactions, I'd like to make it easier for them by disregarding transactions that they have already reversed.I have a table of transactions which will occas