How to eliminate the duplicate rows in the table

Question

How can we eliminate the duplicate rows in the table. Is it possible to write a single query or should we write a pl/sql block to do it

Answer 1

Scope works outwards.
SQL> DECLARE
  2    n NUMBER;
  3  BEGIN
  4    n := 0;
  5    DECLARE
  6      n number;
  7    BEGIN
  8      n := 2;
  9      dbms_output.put_line(n);
10    END;
11  END;
12  /
2
PL/SQL procedure successfully completed.
SQL> DECLARE
  2    n NUMBER;
  3  BEGIN
  4    n := 0;
  5    DECLARE
  6      x number;
  7    BEGIN
  8       dbms_output.put_line(n);
  9       n := 2;
10        dbms_output.put_line(n);
11    END;
12  END;
13  /
0
2
PL/SQL procedure successfully completed.
SQL> ed
Wrote file afiedt.buf
  1  DECLARE
  2    n NUMBER;
  3  BEGIN
  4    n := 0;
  5    DECLARE
  6      x number;
  7    BEGIN
  8       dbms_output.put_line(n);
  9       x := 2;
10     END;
11       dbms_output.put_line(x);
12  EXCEPTION
13     WHEN others THEN      dbms_output.put_line('oh no!');
14* END;
15  /
     dbms_output.put_line(x);
ERROR at line 11:
ORA-06550: line 11, column 27:
PLS-00201: identifier 'X' must be declared
ORA-06550: line 11, column 6:
PL/SQL: Statement ignored
SQL> Cheers, APC