Update on same row

Question

Can someone help me to solve update on table
SQL> select * from emp_addr;
EMP_NAME        EMP_ADD
SAM             15, Telok Kurau Rd
SAM             205,Alexandra Rd
JON             78, Sin Ming Dr
ADAM            803, Coton Gren rd
ADAM            Ubi Rd 4
ADAM            Defu Lane 10
6 rows selectedThe output should be like
SQL> select * from emp_addr;
EMP_NAME        EMP_ADD
SAM_1             15, Telok Kurau Rd
SAM_2             205,Alexandra Rd
JON_1             78, Sin Ming Dr
ADAM_1            803, Coton Gren rd
ADAM_2            Ubi Rd 4
ADAM_3            Defu Lane 10
6 rows selectedrgds
saaz

Answer 1

merge into t
using (select rowid
            , emp||'_'||row_number() over (partition by emp
                                               order by emp_add
                                          ) new_emp
        from t
      ) x
  on (t.rowid = x.rowid)
when matched then update set emp = new_emp
;