Question

How do I remove duplicates from the table where all the columns are significant apart from PK.

declare @dummy table
(
   pk int,
   a char(1),
   b char(1),
   c char(1)
)

insert into @dummy 
select 1, 'A', 'B', 'B' union all
select 2, 'A', 'B', 'B' union all
select 3, 'P', 'Q', 'R' union all
select 4, 'P', 'Q', 'R' union all
select 5, 'X', 'Y', 'Z' union all
select 6, 'X', 'Y', 'Z' union all
select 7, 'A', 'B', 'Z' 

what I get with out distinction:

select * from @dummy

pk          a    b    c
----------- ---- ---- ----
1           A    B    B
2           A    B    B
3           P    Q    R
4           P    Q    R
5           X    Y    Z
6           X    Y    Z
7           A    B    Z

What I’d like is:

select ... do magic ....

pk          a    b    c
----------- ---- ---- ----
1           A    B    B
3           P    Q    R
5           X    Y    Z
7           A    B    Z

Answer 1

Found it:

select min(pk), a, b, c 
from @dummy 
group by a, b, c