Flag Dupplicate Records

[Ananth]

I have a supplier database (extract from AP) with multiple records for a
single supplier. I have a field titled Flag. This flag field is to populated
with “X†for one single record of a supplier , other records for same
supplier with “Yâ€, Literally meaning flagging of duplicates . How to
achieve this by a single query

 

[Allen Browne]

There are many aspects to solving this problem (e.g. how you determine
'duplicate', when the names may be slightly different), so you will need to
sort out the details yourself, but the basic idea is to use a subquery to
determine the duplicates. You can then change it to an Update query to flag
the records.

Here's an example to work from:
http://allenbrowne.com/subquery-01.html#DeDuplicate
It uses a Delete query to remove the duplicates, rather than an Update query
to flag them.