Generating duplicates using more than one condition

Question

dear experts I have the following sample data below
create table tbl_one
  p_id number(30),
  c_id number(30),
  location_a varchar2(300),
  flag varchar2(1)
insert into tbl_one
  (p_id, c_id, location_a, flag)
values
  (1, 112, 'ref_1', '1');
insert into tbl_one
  (p_id, c_id, location_a, flag)
values
  (1, 113, 'ref_1', '1');
insert into tbl_one
  (p_id, c_id, location_a, flag)
values
  (1, 114, 'ref_2', '1');
insert into tbl_one
  (p_id, c_id, location_a, flag)
values
  (2, 115, 'ref_3', '1');
insert into tbl_one
  (p_id, c_id, location_a, flag)
values
  (2, 116, 'ref_3', '1');
insert into tbl_one
  (p_id, c_id, location_a, flag)
values
  (2, 117, 'ref_4', '1');this is the output I desire below
PID    C_ID    LOCATION_A     FLAG
1        112     ref_1                 1
1        113     ref_1                 1
2        115     ref_3                 1
2        116     ref_3                 1basically the output is obtained for all cases where the location_A and flag are duplicated in the same pid
I need help with the query. All help is appreciated. Thank you

Answer 1

select p_id, c_id, location_a, flag from
select p_id, c_id, location_a, flag, count('Dracula') over (partition by p_id, location_a, flag) cnt
from tbl_one
where cnt > 1
order by p_id, c_id
P_ID     C_ID     LOCATION_A     FLAG
1     112     ref_1     1
1     113     ref_1     1
2     115     ref_3     1
2     116     ref_3     1