SQL> SELECT * FROM TEST_TABLE;

     COL_A COL_B
---------- --------------------
         3 C
         1 A
         2 B
         4 D
         5 E
         6 F
         7 G
         8 H
         9 I
        10 J
        11 K

     COL_A COL_B
---------- --------------------
        12 L
        13 M

13 rows selected.

SQL> SELECT * FROM TARGET_TABLE;

     COL_C COL_D
---------- --------------------
         3 C
         1 A
         2 B

3 rows selected.

SQL> declare
  2  cursor c_test_tab is 
  3  select col_A, col_B from test_table;
  4  my_rec c_test_tab%rowtype;
  5   
  6  upd_count number := 0;
  7  ins_count number := 0;
  8  c_colA test_table.col_A%type;
  9  c_colB test_table.col_B%TYPE;
 10  begin
 11  open c_test_tab;
 12  loop
 13  fetch c_test_tab into my_rec;
 14  c_colA := my_rec.COL_A;
 15  c_colB := my_rec.COL_B;
 16  
 17  update TARGET_TABLE set COL_C=c_COLA,
 18  COL_D = C_COLB
 19  where col_C=my_rec.COL_A;
 20  if sql%found then
 21  upd_count := upd_count + 1; 
 22  else
 23  insert into TARGET_TABLE values (c_COLA, c_COLB);
 24  ins_count := ins_count + 1;
 25  end if;
 26  exit when c_test_tab%notfound;
 27  end loop;
 28  dbms_output.put_line('Updated : ' ||to_char(upd_count));
 29  dbms_output.put_line('Inserted : ' ||to_char(ins_count));
 30  close c_test_tab;
 31  end;
 32  /
Updated : 4
Inserted : 10

PL/SQL procedure successfully completed.

SQL> SELECT * FROM TARGET_TABLE;

     COL_C COL_D
---------- --------------------
         3 C
         1 A
         2 B
         4 D
         5 E
         6 F
         7 G
         8 H
         9 I
        10 J
        11 K

     COL_C COL_D
---------- --------------------
        12 L
        13 M

13 rows selected.