Oracle 18c

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CREATE TABLE mytable(
   PARENT_ID INTEGER  NOT NULL 
  ,ID        INTEGER  NOT NULL
  ,YR_MONTH  INTEGER  NOT NULL
  ,REWARD    INTEGER  NOT NULL
);

begin
INSERT INTO mytable(PARENT_ID,ID,YR_MONTH,REWARD) VALUES (1,11,201601,3);
INSERT INTO mytable(PARENT_ID,ID,YR_MONTH,REWARD) VALUES (1,12,201605,9);
INSERT INTO mytable(PARENT_ID,ID,YR_MONTH,REWARD) VALUES (1,13,201609,12);
INSERT INTO mytable(PARENT_ID,ID,YR_MONTH,REWARD) VALUES (2,21,201601,6);
INSERT INTO mytable(PARENT_ID,ID,YR_MONTH,REWARD) VALUES (2,22,201605,9);
INSERT INTO mytable(PARENT_ID,ID,YR_MONTH,REWARD) VALUES (2,23,201609,9);
INSERT INTO mytable(PARENT_ID,ID,YR_MONTH,REWARD) VALUES (3,31,201601,15);
INSERT INTO mytable(PARENT_ID,ID,YR_MONTH,REWARD) VALUES (3,32,201605,9);
INSERT INTO mytable(PARENT_ID,ID,YR_MONTH,REWARD) VALUES (3,33,201609,12);
INSERT INTO mytable(PARENT_ID,ID,YR_MONTH,REWARD) VALUES (3,34,201610,9);
end;
/
1 rows affected

	select 
		t.*,
		case 
			when reward = 9 
			and sum(case when reward >= 9 then 1 else 0 end)  over(partition by parent_id order by yr_month) = 1
		then 1 else 0 end reward_status
	from mytable t


PARENT_ID
ID
YR_MONTH
REWARD
REWARD_STATUS


1
11
201601
3
0

1
12
201605
9
1

1
13
201609
12
0

2
21
201601
6
0

2
22
201605
9
1

2
23
201609
9
0

3
31
201601
15
0

3
32
201605
9
0

3
33
201609
12
0

3
34
201610
9
0

PARENT_ID	ID	YR_MONTH	REWARD	REWARD_STATUS
1	11	201601	3	0
1	12	201605	9	1
1	13	201609	12	0
2	21	201601	6	0
2	22	201605	9	1
2	23	201609	9	0
3	31	201601	15	0
3	32	201605	9	0
3	33	201609	12	0
3	34	201610	9	0