You can use various aggregate functions.
Example: Choose first occurrence of duplicated column
Select Col1, Col2, FIRST(Col3) As Col3A, Col4
From Table
Group By Col1, Col2, Col4
You could use LAST to get the last value, MIN to get the minimum value or MAX to get the maximum value of the duplciated column.
I suggest that future postings about Access be made in one of the Access forums. This forum focuses on ANSI standard SQL which Access isn't! Terry L. Broadbent
faq183-874 contains some tips and ideas for posting questions in these forums. Please review it and comment if you have time.
NOTE: Reference to the FAQ is part of my signature and is not directed at any individual.