Help Finding Duplicate Of Reversed Fields

Hi

This is my first post and i searched to try and find an answer on the forums but can't seem to find one so thought i'd ask to see if anyone is able to help. Sorry if this has been answered before and i've been a bit thick not been able to find it. anyway here's my question...

I have 2 fields i want to check in my database DOB1 and DOB2 (date of birth of applicant 1 and date of birth of applicant 2.

i've written a query that looks for any records where the data in DOB1 and DOB2 match the data in another record for DOB1 and DOB2. i hope that makes sense. this is what i've written.

In (SELECT [App1 DOB] FROM [Data] As Tmp GROUP BY [App1 DOB],[App2 DOB] HAVING Count(*)>1 And [App2 DOB] = [Data].[App2 DOB])

this seems to work but please feel free to correct me.

Now the part i'm struggling with is trying to find duplicates where the fields have been reversed. eg App1 DOB and App2 DOB are the same as App1 DOB and App2 DOB in another record but applicant 1's Date of birth has been stored as Applicant 2 and Applicant 2 is now stored as Applicant 1. i hope thats not to confusing.

Basically i'm trying to check for duplicate mortgage applications in the database but sometimes applicant 1 and applicant 2 are reversed.

Any help would be greatly appreciated.

Thanks