To display unique records

Question

if a table consists of records like
1 upendra 100
1 upendra 100
1 upendra 100
2 upen 200
2 upen 200
3 upend 300
3 upend 300
with a query i want to make the records in the above table like
1 upendra 100
2 upen 200
3 upend 300
i.e., i need only unique rows(remaining should be deleted) how can i do it
Thanks
upendra
Message was edited by: upendra

Answer 1

SQL> create table tbl1 as
  2  select 1 c1, 'upendra' c2,  100 c3 from dual union all
  3  select 1 c1, 'upendra' c2,  100 c3 from dual union all
  4  select 1 c1, 'upendra' c2,  100 c3 from dual union all
  5  select 2 c1, 'upen' c2, 200 c3 from dual union all
  6  select 2 c1, 'upen' c2, 200 c3 from dual union all
  7  select 3 c1, 'upend' c2, 300 c3 from dual union all
  8  select 3 c1, 'upend' c2, 300 c3 from dual ;
Table created.
SQL>
SQL> select c1, c2, c3, count(*)
  2  from tbl1
  3  group by c1, c2, c3
  4  having count(*)>1;
        C1 C2              C3   COUNT(*)
         1 upendra        100          3
         2 upen           200          2
         3 upend          300          2
SQL>
SQL> delete tbl1
  2  where rowid in (select lead(rowid) over (partition by c1,c2,c3 order by null) from tbl1);
4 rows deleted.
SQL>
SQL> select c1, c2, c3
  2  from tbl1;
        C1 C2              C3
         1 upendra        100
         2 upen           200
         3 upend          300
SQL> Nicolas.