Remove duplicates based on multiple columns

Question

I've got a multiple fields Primary Key that consists of (col1,col2,col3). However, before the PK was added, there have been a lot of duplicates added which need to be removed.

So for my table if I have:

Col1 Col2 Col3
---- ---- ----
  2    3   3
  2    3   3
  2    3   4
  2    4  null
  2    4  null

the query should result in

 Col1 Col2 Col3
 ---- ---- ----
  2    3   3
  2    3   4
  2    4  null

Only 3rd column is nullable.

score 0 · Answer 1 · answered May 09 '19 at 09:31

0

use distinct

select distinct col1, col2, col3
from tablename

answered May 09 '19 at 09:31

Fahmi

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2

This doesn't actually _remove_ any records, it only presents the view the OP wants. – Tim Biegeleisen May 09 '19 at 09:31

Remove duplicates based on multiple columns

1 Answers1